Question

cosx=sin2x solve

Answer 1

x = 60⁰ + 360⁰n, x = 300⁰ + 360⁰n, where n is any integer

Read more: http://wiki.answers.com/Q/How_do_you_solve_the_following_equation_using_identities_sin2x-sinx_equals_0#ixzz1VK6Ihoyj

Answer 2

i got sinx=1/2

Answer 3

oh i must have typed the wrong equation then

Answer 4

sorry

Answer 5

no problem thanks!

Answer 6

:D

Answer 7

\[\cos(x) = \sin(2x) \iff \cos(x) = 2\sin(x)\cos(x)\]\[\iff \cos(x)-2\sin(x)\cos(x) = 0\iff \cos(x)(1-2\sin(x)) = 0\]

This gives either:
\[\cos(x) = 0 \Rightarrow x = \frac{\pi}{2}, \frac{3\pi}{2}\]
or
\[1-2\sin(x) = 0 \iff \sin(x) = \frac{1}{2} \Rightarrow x = \frac{\pi}{6}, \frac{5\pi}{6}\]