I have a circle with a radius of 12.5mm
I draw a line that hits the outside of the circle at 60° to the x axis .
I drop a line from that point to the x axis , that line is 90° to the x axis .
The tan of 60° is say .577
Where that dropped line hits the axis , is it 57.7% of the radius ?
ie is the distance from the centre of the circle to the dropped line 7.2mm ?

Seems intuitively correct
Help Please

Brett

It’s exactly half the radius, Thomo.

Thanks for the reply Peak
I know I didn’t explain it well
Your diagram has the hypotenuse at 12.5mm
I need the Vert side 12.5 , The hypotenuse will be longer
I needed to know the length of the shortest side

Brett

The tan of 60 degrees is 1.73, it’s not a variable.

For the problem as originally stated you need the Cosine of 60 degrees, which is 0.5.

For the re-stated problem you need the cotangent of 60 degrees, which is 1/Tan 60 = 1/sqrt(3) = about 0.577.

So your number is right, just the name was wrong.

Perhaps an easier way is to use the rule of sines.

12.5/sin 60 = x/sin 30

x = 7.22

Hi all thanks for the answers
This was what I meant

circle and tangent.pdf

I was trying to find how far into the circle a Tangent ? at 60° comes int the circle
The diagram I up loaded is from a site
https://www.desmos.com/calculator/qqzgsg1×8o
but it wont let me be precis
Thanks for the advice ….
It seems to be around the 3mm

Brett

Thomo said:

I was trying to find how far into the circle a Tangent ? at 60° comes int the circle
The diagram I up loaded is from a site
https://www.desmos.com/calculator/qqzgsg1×8o
but it wont let me be precis
Thanks for the advice ….
It seems to be around the 3mm

Brett

I still don’t understand what you want.

A tangent at any point won’t come into the circle at all. The green and purple lines are tangents.

The Rev Dodgson said:

Thomo said:

I was trying to find how far into the circle a Tangent ? at 60° comes int the circle
The diagram I up loaded is from a site
https://www.desmos.com/calculator/qqzgsg1×8o
but it wont let me be precis
Thanks for the advice ….
It seems to be around the 3mm

Brett

I still don’t understand what you want.

A tangent at any point won’t come into the circle at all. The green and purple lines are tangents.

I’m confused.

Thomo said:

I was trying to find how far into the circle a Tangent ? at 60° comes int the circle
The diagram I up loaded is from a site
https://www.desmos.com/calculator/qqzgsg1×8o
but it wont let me be precis
Thanks for the advice ….
It seems to be around the 3mm

Brett

If you want the x coordinate of the two blue dots, it’s 21.65, assuming the radius is 25.

The Rev Dodgson said:

Thomo said:

I was trying to find how far into the circle a Tangent ? at 60° comes int the circle
The diagram I up loaded is from a site
https://www.desmos.com/calculator/qqzgsg1×8o
but it wont let me be precis
Thanks for the advice ….
It seems to be around the 3mm

Brett

If you want the x coordinate of the two blue dots, it’s 21.65, assuming the radius is 25.

Thats what Im after
So glad you could translate my gibberish
Its 21.65 if the blue and green lines are at 60° to the x axis yes ?

Brett

I need 20mm max damn
I cannot change the angle or the radius

Trying to design a new balustrading rail for a specific application
I may have just found out why it does not exist

Brett

Thomo said:

The Rev Dodgson said:

Thomo said:

I was trying to find how far into the circle a Tangent ? at 60° comes int the circle
The diagram I up loaded is from a site
https://www.desmos.com/calculator/qqzgsg1×8o
but it wont let me be precis
Thanks for the advice ….
It seems to be around the 3mm

Brett

If you want the x coordinate of the two blue dots, it’s 21.65, assuming the radius is 25.

Thats what Im after
So glad you could translate my gibberish
Its 21.65 if the blue and green lines are at 60° to the x axis yes ?

Brett

Yes, but it seems easier to me to just look at the two radii, which should be at 30 degrees to the x axis.

Of course nver occurred to me.
Its got to do with climable members

Thanks
Rev
Sibeen
Peak

Brett

Thomo said:

Thanks
Rev
Sibeen
Peak

Brett

no worries.

speaking of maths, my daughter had a maths problem… make 100 using 7,7,7,7 it took me about three thousand calculations and ten minutes and I couldn’t come up with the answer… my ten yr old son came out with an answer in about 63 seconds… I spanked him and told him off for being a smartarse…

Arts said:

speaking of maths, my daughter had a maths problem… make 100 using 7,7,7,7 it took me about three thousand calculations and ten minutes and I couldn’t come up with the answer… my ten yr old son came out with an answer in about 63 seconds… I spanked him and told him off for being a smartarse…

Congrats to Arts Minor.

I didn’t get it either.

Even after I looked it up and found it should be 7,7,7,7,1.

The Rev Dodgson said:

Arts said:

speaking of maths, my daughter had a maths problem… make 100 using 7,7,7,7 it took me about three thousand calculations and ten minutes and I couldn’t come up with the answer… my ten yr old son came out with an answer in about 63 seconds… I spanked him and told him off for being a smartarse…

Congrats to Arts Minor.

I didn’t get it either.

Even after I looked it up and found it should be 7,7,7,7,1.

the problem didn’t have the 1… did you get the four sevens (sans 1) solution?

I have an unbeaten record against this kid in chess, but he has come close a couple of times. I might have to retire soon to keep my undefeated record in tact..

Arts said:

The Rev Dodgson said:

Arts said:

speaking of maths, my daughter had a maths problem… make 100 using 7,7,7,7 it took me about three thousand calculations and ten minutes and I couldn’t come up with the answer… my ten yr old son came out with an answer in about 63 seconds… I spanked him and told him off for being a smartarse…

Congrats to Arts Minor.

I didn’t get it either.

Even after I looked it up and found it should be 7,7,7,7,1.

the problem didn’t have the 1… did you get the four sevens (sans 1) solution?

I have an unbeaten record against this kid in chess, but he has come close a couple of times. I might have to retire soon to keep my undefeated record in tact..

I see what you did there in separating tact.

Arts said:

The Rev Dodgson said:

Arts said:

speaking of maths, my daughter had a maths problem… make 100 using 7,7,7,7 it took me about three thousand calculations and ten minutes and I couldn’t come up with the answer… my ten yr old son came out with an answer in about 63 seconds… I spanked him and told him off for being a smartarse…

Congrats to Arts Minor.

I didn’t get it either.

Even after I looked it up and found it should be 7,7,7,7,1.

the problem didn’t have the 1… did you get the four sevens (sans 1) solution?

I have an unbeaten record against this kid in chess, but he has come close a couple of times. I might have to retire soon to keep my undefeated record in tact..

Damn

I’ll have to try again now.

Good plan with the chess.

The Rev Dodgson said:

Arts said:

The Rev Dodgson said:

Congrats to Arts Minor.

I didn’t get it either.

Even after I looked it up and found it should be 7,7,7,7,1.

the problem didn’t have the 1… did you get the four sevens (sans 1) solution?

I have an unbeaten record against this kid in chess, but he has come close a couple of times. I might have to retire soon to keep my undefeated record in tact..

Damn

I’ll have to try again now.

Good plan with the chess.

what’s the solution?

party_pants said:

The Rev Dodgson said:

Arts said:

the problem didn’t have the 1… did you get the four sevens (sans 1) solution?

I have an unbeaten record against this kid in chess, but he has come close a couple of times. I might have to retire soon to keep my undefeated record in tact..

Damn

I’ll have to try again now.

Good plan with the chess.

what’s the solution?

It stems from four sevens.

party_pants said:

The Rev Dodgson said:

Arts said:

the problem didn’t have the 1… did you get the four sevens (sans 1) solution?

I have an unbeaten record against this kid in chess, but he has come close a couple of times. I might have to retire soon to keep my undefeated record in tact..

Damn

I’ll have to try again now.

Good plan with the chess.

what’s the solution?

7/.7 × 7/.7

roughbarked said:

party_pants said:

The Rev Dodgson said:

Damn

I’ll have to try again now.

Good plan with the chess.

what’s the solution?

It stems from four sevens.

yes dear, closest I can get is 98. What’s the answer?

ChrispenEvan said:

party_pants said:

The Rev Dodgson said:

Damn

I’ll have to try again now.

Good plan with the chess.

what’s the solution?

7/.7 × 7/.7

That seems outside the rules to me.

party_pants said:

ChrispenEvan said:

party_pants said:

what’s the solution?

7/.7 × 7/.7

That seems outside the rules to me.

rules are for the straitjacketed amung us.

Arts, if the young bloke is interested in chess maybe guide him to this youtube channel.

https://www.youtube.com/channel/UCL5YbN5WLFD8dLIegT5QAbA

party_pants said:

roughbarked said:

party_pants said:

what’s the solution?

It stems from four sevens.

yes dear, closest I can get is 98. What’s the answer?

Best I can do so far is using 6 sevens.

party_pants said:

ChrispenEvan said:

party_pants said:

what’s the solution?

7/.7 × 7/.7

That seems outside the rules to me.

Looks fair enough to me.

Just wish I’d thought of it.

ChrispenEvan said:

party_pants said:

ChrispenEvan said:

7/.7 × 7/.7

That seems outside the rules to me.

rules are for the straitjacketed amung us.

Well, fuck you all then. I’m off to cook some potatoes.

The Rev Dodgson said:

party_pants said:

roughbarked said:

It stems from four sevens.

yes dear, closest I can get is 98. What’s the answer?

Best I can do so far is using 6 sevens.

my sons solution is not unlike boris solution (probably googled)

here in black for no spoilers 77/.77

Arts said:

The Rev Dodgson said:

party_pants said:

yes dear, closest I can get is 98. What’s the answer?

Best I can do so far is using 6 sevens.

my sons solution is not unlike boris solution (probably googled)

here in black for no spoilers 77/.77

I like that more than the Boris version.

Arts said:

The Rev Dodgson said:

party_pants said:

yes dear, closest I can get is 98. What’s the answer?

Best I can do so far is using 6 sevens.

my sons solution is not unlike boris solution (probably googled)

here in black for no spoilers 77/.77

i googled.

sibeen said:

Arts, if the young bloke is interested in chess maybe guide him to this youtube channel.

https://www.youtube.com/channel/UCL5YbN5WLFD8dLIegT5QAbA

thanks.. he does go to chess class occasionally (when we have time) and he does an extension maths class at the near by uni, which is good for him.. I just hope he makes enough money in the future to keep his mother in the lifestyle to which she has become accustomed…

Arts said:

sibeen said:

Arts, if the young bloke is interested in chess maybe guide him to this youtube channel.

https://www.youtube.com/channel/UCL5YbN5WLFD8dLIegT5QAbA

thanks.. he does go to chess class occasionally (when we have time) and he does an extension maths class at the near by uni, which is good for him.. I just hope he makes enough money in the future to keep his mother in the lifestyle to which she has become accustomed…

Probably better send him to a class in advanced Muskology as well then.

The Rev Dodgson said:

Arts said:

sibeen said:

Arts, if the young bloke is interested in chess maybe guide him to this youtube channel.

https://www.youtube.com/channel/UCL5YbN5WLFD8dLIegT5QAbA

thanks.. he does go to chess class occasionally (when we have time) and he does an extension maths class at the near by uni, which is good for him.. I just hope he makes enough money in the future to keep his mother in the lifestyle to which she has become accustomed…

Probably better send him to a class in advanced Muskology as well then.

sage

The Rev Dodgson said:

Arts said:

The Rev Dodgson said:

Best I can do so far is using 6 sevens.

my sons solution is not unlike boris solution (probably googled)

here in black for no spoilers 77/.77

I like that more than the Boris version.

his reasoning “I thought 77/77 equals one so I just moved the decimal place” so I spanked him even harder and banned him from dessert for a week

Arts said:

The Rev Dodgson said:

Arts said:

my sons solution is not unlike boris solution (probably googled)

here in black for no spoilers 77/.77

I like that more than the Boris version.

his reasoning “I thought 77/77 equals one so I just moved the decimal place” so I spanked him even harder and banned him from dessert for a week

Yeah, the little bugger deserves it.

Making his elders and betters feel stupid by pointing out how obvious the answer was.

The Rev Dodgson said:

Arts said:

The Rev Dodgson said:

Congrats to Arts Minor.

I didn’t get it either.

Even after I looked it up and found it should be 7,7,7,7,1.

the problem didn’t have the 1… did you get the four sevens (sans 1) solution?

I have an unbeaten record against this kid in chess, but he has come close a couple of times. I might have to retire soon to keep my undefeated record in tact..

Damn

I’ll have to try again now.

Good plan with the chess.

777/7 = 100

Michael V said:

The Rev Dodgson said:

Arts said:

the problem didn’t have the 1… did you get the four sevens (sans 1) solution?

I have an unbeaten record against this kid in chess, but he has come close a couple of times. I might have to retire soon to keep my undefeated record in tact..

Damn

I’ll have to try again now.

Good plan with the chess.

777/7 = 100

cough

I wonder what 700/7 equals now days.

The Rev Dodgson said:

Arts said:

The Rev Dodgson said:

I like that more than the Boris version.

his reasoning “I thought 77/77 equals one so I just moved the decimal place” so I spanked him even harder and banned him from dessert for a week

Yeah, the little bugger deserves it.

Making his elders and betters feel stupid by pointing out how obvious the answer was.

My solution is different. But it’s incorrect…

:)

The Rev Dodgson said:

Arts said:

The Rev Dodgson said:

I like that more than the Boris version.

his reasoning “I thought 77/77 equals one so I just moved the decimal place” so I spanked him even harder and banned him from dessert for a week

Yeah, the little bugger deserves it.

Making his elders and betters feel stupid by pointing out how obvious the answer was.

I guess it’s a little like that bus question… where the kids all get it and adults (allegedly) struggle….

which way is the bus going?

I reckon 7 × 7 + 7 × 7 + 2 = 100 is perfectly valid, if you are allowed to add in other numbers for convenience.

Arts said:

The Rev Dodgson said:

Arts said:

his reasoning “I thought 77/77 equals one so I just moved the decimal place” so I spanked him even harder and banned him from dessert for a week

Yeah, the little bugger deserves it.

Making his elders and betters feel stupid by pointing out how obvious the answer was.

I guess it’s a little like that bus question… where the kids all get it and adults (allegedly) struggle….

which way is the bus going?

In Australia tte doors are always on the left, so it is going towards the right.

Arts said:

The Rev Dodgson said:

Arts said:

his reasoning “I thought 77/77 equals one so I just moved the decimal place” so I spanked him even harder and banned him from dessert for a week

Yeah, the little bugger deserves it.

Making his elders and betters feel stupid by pointing out how obvious the answer was.

I guess it’s a little like that bus question… where the kids all get it and adults (allegedly) struggle….

which way is the bus going?

Right.

party_pants said:

Arts said:

The Rev Dodgson said:

Yeah, the little bugger deserves it.

Making his elders and betters feel stupid by pointing out how obvious the answer was.

I guess it’s a little like that bus question… where the kids all get it and adults (allegedly) struggle….

which way is the bus going?

In Australia tte doors are always on the left, so it is going towards the right.

there is no one on the bus looking at their phone, s I’d say the bus is not in service and stationary

sibeen said:

I wonder what 700/7 equals now days.

Pi.

Arts said:

The Rev Dodgson said:

Arts said:

his reasoning “I thought 77/77 equals one so I just moved the decimal place” so I spanked him even harder and banned him from dessert for a week

Yeah, the little bugger deserves it.

Making his elders and betters feel stupid by pointing out how obvious the answer was.

I guess it’s a little like that bus question… where the kids all get it and adults (allegedly) struggle….

which way is the bus going?

It’s not a bus, it’s a picture.

Arts said:

party_pants said:

Arts said:

I guess it’s a little like that bus question… where the kids all get it and adults (allegedly) struggle….

which way is the bus going?

In Australia tte doors are always on the left, so it is going towards the right.

there is no one on the bus looking at their phone, s I’d say the bus is not in service and stationary

now you’re just being silly.

party_pants said:

I reckon 7 × 7 + 7 × 7 + 2 = 100 is perfectly valid, if you are allowed to add in other numbers for convenience.

But a decimal point is not a number, whereas a 2 is.

The Rev Dodgson said:

party_pants said:

I reckon 7 × 7 + 7 × 7 + 2 = 100 is perfectly valid, if you are allowed to add in other numbers for convenience.

But a decimal point is not a number, whereas a 2 is.

To create 0.77 requires dividing 77 by 100. Moving the decimal point is not really a mathematical function as such, it is just a short-hand way of expressing ‘divide by 100’ using our particular numeral system.

My brain refuses to accept is as a valid solution.

party_pants said:

The Rev Dodgson said:

party_pants said:

I reckon 7 × 7 + 7 × 7 + 2 = 100 is perfectly valid, if you are allowed to add in other numbers for convenience.

But a decimal point is not a number, whereas a 2 is.

To create 0.77 requires dividing 77 by 100. Moving the decimal point is not really a mathematical function as such, it is just a short-hand way of expressing ‘divide by 100’ using our particular numeral system.

My brain refuses to accept is as a valid solution.

Somebody could take a bite out of my mars bar, leaving me with 0.77 of a Mars bar.