How do you find the tangent of an angle without a calculator?
Like a 30 degree angle, whats the diagram or proof for it?
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Here you go...
what about 15 degree?
15 degree is the value of 45 degree minus 30 degree
But you need special identities to calculate for example: sin(45 - 30)
but isnt there a way using a 30 60 90, mabe bisecting the 30 and finding out the tangent of 15..with no calc at all
Unfortunately no, not unless you have values for the sides.
There isnt really a shortcut.
thats what i have so far
Cos 15 will give you the value of bd.
Then Pythagoras will give you the value of ad.
And you are given that (root3)/2 = ad/dc.
So then you can calculate dc.
ahhh great idea
now im simplifying
tan(15) = root( (root3/cos15)^2 - (root3)^2 ) / root3
but without solving the tans and cos and roots...(basically no calc at all)
It did take a lil good old trig to get there.
can i even simplify that besides change the root3^2 to 3?
Tan 15 = ad/root3
= (1/cos 15) - 1
I hope all this helped you.
its all very appreciated!
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