Question

sin ^4 x + 2 sin ^2 x cos ^2 x + cos ^4 x

Answer 1

\(\large sin ^4 x + 2 sin ^2 x cos ^2 x + cos ^4 x=(sin^2x+cos^2x)^2 =(1)^2=1\)

Answer 2

how come (sin^2 x + cos^2 x) ??

Answer 3

all you need to do is factor it out...
notice the trig expression you gave is of this form: x^2 + 2xy + y^2
and that can be factored to (x + y)^2

Answer 4

ok