- #1
Peter G.
- 442
- 0
Hi,
I had to solve without the aid of a calculator:
2cos(x) = sin(2x)
What I did was perform the following substitution:
2cos(x) = 2sin(x)cos(x)
I then canceled and got:
sin (x) = 1
For 0 to 3pi,
I got two answers, pi/2 and 5pi/2.
I did not get one of the answers. Why?
What did I do wrong?
Thanks!
I had to solve without the aid of a calculator:
2cos(x) = sin(2x)
What I did was perform the following substitution:
2cos(x) = 2sin(x)cos(x)
I then canceled and got:
sin (x) = 1
For 0 to 3pi,
I got two answers, pi/2 and 5pi/2.
I did not get one of the answers. Why?
What did I do wrong?
Thanks!