ILL GIVE YOU BRAINLIESTwhich expression is equivalent to cos(1.4x)-cos(0.6x)? A: -2sin x sin(0.4x)
B: 2sin x sin(0.4x)
C: -2cos x cos(0.4x)
D: 2cos x cos(0.4x)

A. -2sin x sin(0.4x)

Explanation:

I got it correct in my test :)

see attached

step-by-step explanation:

given the function as;

write the equation replacing f(x) with y

form   and fill a table containing values of y with corresponding values of x

you can take a range for   values of x as -3≤x≤3

solving for x=-3

for x=-2

repeat the same procedure to get the values of y for the remaining ,x=-1 to x=3

plot the values of y against values   of x and obtain the following graph