All are correct except for b). Why did you halve the interval?
Given f(x) = cosx, 0≤x≤4pi, sketch and give range in each case
a) y = 2f(x) + 1
range of -1≤y≤3
b) y = f(2x)
squeezed along x axis so there are 8 turning points, range of -1/2≤y≤1/2
c) y = -f(x)
same range, simply turned over
d) y = f(x + pi)
same range, graph is moved 1pi to the left
Are these right??? :/