Question

sin2x cosx + cos 2x sin x= -1

Answer 1

that is sin(2x+x) = 1

Answer 2

can you solve that?

Answer 3

woops -1 sorry so sin(2x+x) = sin(3x) = -1
so 3x = -pi//2

Answer 4

I think someone else is about to same the same thing but write it cooler:)

Answer 5

LOL -_-

Answer 6

ha

Answer 7

Tbh i'm using identities and i don't know if it's making it more complicated, lol..

Answer 8

I used sin(a+b) = sin(a)cos(b) + cos(a)sin(b)

Answer 9

\[\sin(2x)\cos(x)+\cos(2x)\sin(x)=-1\]\[2\sin(x)\cos(x)*\cos(x)+(1-2\sin^2(x))*\sin (x)=-1\]\[2\sin(x)\cos^2(x)-\sin(x)-2\sin^3(x)=-1\]\[\sin(x)(2\cos^2(x)-1-2\sin^2(x))=-1\]\[\sin(x)(\cos(2x)-2\sin^2(x))=-1\]

Yeah no....

Answer 10

sin(3x) = sin(2x+x) = sin(2x)cos(x) + cos(2x)sin(x)

Answer 11

Oh is that right...lmao ok.