f(x)=-8x^4-5x^3 +3 for concavity and inflection points.

f(x)=-8x^4-5x^3 +3

f'(x)=-32x^3-15x^2

f''(x)=-96x^2-30x

can someone explain to me what exactly Inflection Points are?

is it like critical points for the first derivative but those are for the second one?

i mean, making f''(x) = 0 and get 2 numbers and those are the Inflection Points?