Question

What is the vertex of the parabola y = 5(x + 4)^
2 + 1 ?

Answer 1

you have to differentiate and equate to 0.

expanding the equation helps to make differentiating easier

Answer 2

can you show me?

Answer 3

simplifying: 5x^2 + 40x + 81

Answer 4

got that?

Answer 5

yep

Answer 6

then, differentiate w.r.t x.
10x + 40

Answer 7

okay...

Answer 8

equating that to 0 would give you the x-coordinate of the stationary point

Answer 9

hence x = -4

Answer 10

put that into your original equation to get the y-coordinate

Answer 11

so the vertex is (-4,1)

Answer 12

thanks!