Question

If f(x)=-2x^2+5x-3 and g(x) is the reflection of f(x) across the y-axis, then an equation of g is which of the following

Answer 1

To reflect a function across the y-axis you have to change

$x\mapsto -x$

So, the function becomes

$f(x)=-2x^2+5x-3 \mapsto f(-x)=-2(-x)^2+5(-x)-3=-2x^2-5-3$