- #1
rsaad
- 77
- 0
for cos y the critical points are n*pi - 0.5*pi
for cos 2x, the critical points should be n/2 * pi - 0.25*pi
because if I set y=2x = n*pi - 0.5*pi , I get the eq in red for x.
However if I do it graphically, I just get n*pi - 0.25*pi.
The question: why algebraically I am constrained to use the even number n but graphically, there is no restriction on n?
for cos 2x, the critical points should be n/2 * pi - 0.25*pi
because if I set y=2x = n*pi - 0.5*pi , I get the eq in red for x.
However if I do it graphically, I just get n*pi - 0.25*pi.
The question: why algebraically I am constrained to use the even number n but graphically, there is no restriction on n?