Prove : Cos^4A+sin^4A=1/4(3+cos4A)

1 = (sin^2 A + cos^2 A)^2 = sin^4 A + cos^4 A + 2 sin^2 A cos^2 A

so

sin^4 A + cos^4 A

= 1 - 1/2 sin^2 2A

= 1 - 1/4 (1- cos 4A)

= 1/4 (3+cos 4A)

Step-by-step explanation:

hope I helped

answer: i literally just answered this question but they want me to do it again

step-by-step explanation:

look at the picture.

y-intercept for the function on a picture is 4 → point (0, 4).

y-intercept for the function

is for x = 0. substitute:

y-intercept is 8 → point (0, 8).