Which of the following is an even function?

g (x) = (x - 1) 2 + 1

g (x) = 2x2 + 1

g (x) = 4x + 2

g (x) = 2x

Even means g (-x) = g (x)

replace x with - x and see if it simplifies to original functin

g (-x) = (-x-1) ²+1

g (-x) = ((-1) (x+1)) ²+1

g (-x) = (x+1) ²+1

nope

g (x) = 2x²+1

g (-x) = 2 (-x) ²+1

g (-x) = 2x²+1

yep

we are done

answer is 2nd one