Question

What is the axis of symmetry for f(x)=2x^2+4x+2

Answer 1

The axis of symmetry is x=t where t is a constant

for f(x)=ax²+bx+c, the value of t is $\dfrac{-b}{2a}$

so given
f(x)=2x²+4x+2
a=2
b=4

so t is $\dfrac{-4}{2(2)}$ or $\dfrac{-4}{4}$ or -1
the axis of symmetry is x=-1

Answer 2

Hello : 
f(x)=2x²+4x+2 = 2(x²+2x+1)
f(x) = 2(x+1)²...( vertex form)
the axis of symmetry is the line for equation : x = -1