Question

how do i solve for sinxcosx + 2cosx = 0

Answer 1

There is a way you can factor this some. Factor it slightly and then set each factor equal to 0 and solve. Can you see what you factor out?

Answer 2

cosx

Answer 3

Right. So that gives you

cosx(sinx + 2) = 0 so you would set each factor equal to 0

cosx = 0
sinx + 2 = 0

Of course that bottom factor has an issue with it if you maybe recognize it.

Answer 4

yes the plus 2, so how do i solve for that?

Answer 5

You cant.
sinx =-2

But the range of the sin function isonly [-1,1], meaning there is no answer for that factor. That means you're only answers will come from cosx = 0

Answer 6

so the answer is just pi/2 and 3pi/2?

Answer 7

Yep : )

Answer 8

woohoo thanks! i appreciate it

Answer 9

Yeah, np :3