SOLUTION: Angle A is acute and such that tanA=√6/3. (a) Show clearly that the exact value of sin A can be written in the form 1/5√k and state the value of k. (b) Hence, or

Algebra ->  Equations -> SOLUTION: Angle A is acute and such that tanA=√6/3. (a) Show clearly that the exact value of sin A can be written in the form 1/5√k and state the value of k. (b) Hence, or       Log On


   



Question 401144: Angle A is acute and such that tanA=√6/3.
(a) Show clearly that the exact value of sin A can be written in the form 1/5√k and state the value of k.
(b) Hence, or otherwise, show that the value of cos2A is exactly 1/5

Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
(a)
==> .
(b)cos+%282A%29+=+1-2sin%5E2%28A%29+=+1+-+2%2A%2810%2F25%29+=+1+-+4%2F5+=+1%2F5