Question 257759: How to solve this problem and the steps w/five key points?
y = Sin 4x? I'm a beginner can u help? Answer by drk(1908) (Show Source):
You can put this solution on YOUR website! This you really can't solve. You can simplify or graph.
(i)
--
Now 4x = 2x + 2x, so we get
(ii)
we have an identity:
sin(A+B) = sinA cosB + sinB cosA
or in our case
(iii)
But these are the same, so we can write
(Iv)
--
Now 2x = x + x, so we get
(v)
we have an identity:
sin(A+B) = sinA cosB + sinB cosA
or in our case
(vi)
But these are the same, so we can write
(vii)
From (iv) and (vii), we get
(