# calculus

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at what point do the graph of the function f(x)=(x^2)+4x-1 have a horizontal tangent?

• calculus -

That is a parabola. It is horizontal at the vertex.

• calculus -

Of course you could do it the sophisticated way, where the derivative is zero

f' = 2 x + 4
= 0 when x = -2
then
y = -5

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