How do you graph #f(x) = 3 Sin x + 4 Cos x#?

1 Answer
Apr 9, 2016

Draw the sine wave for the equation f(x) = 5 sin (x + #alpha#), where #sin alpha = 4/5 and cos alpha = 3/5#. The is the graph. It is periodic, with period #2pi#, The amplitude of the wave is 5.

Explanation:

With the notations, in the answer, #f(x) = 5 (sin x cos alpha + cos x sin alpha ) = 5 sin (x+alpha)#.
This is the equation for the sine wave with period #2pi# and amplitude 5
the graph cuts the f-axis at (0, 5 sin #alpha#)..