Question

PreCalc & Trig Help!
Picture below.
I did one like this already, but for some reason I just can't figure this one out. :/

Answer 1

B

Answer 2

can you tell me how you found that so i know for the rest of the ones like it ?

Answer 3

let x= o-->sin(o) =0 and 2x=0 ---> sin2x =0 . you can conclude that sinx = sin2x when x =0.
other solutions are not right because there are some pairs not satisfy sinx =sin2x.

Answer 4

Okay, thank you.

Answer 5

for example: in A)if x =pi/2---> sin(pi,2) = 1 but sin 2(pi/2) = sinpi=0

Answer 6

ok, I'm glad you understand

Answer 7

yup thanks!