# Math Help - Derivative

1. ## Derivative

Using the short cut rule find the derivative of the following functions then simplify results. Please explain how you got it

m(x)=4x^3-15x^2+x-7

h(x)=(3x^2+7)(x^3-x)

g(x)=x

s(t)=4^t5+20t

2. Originally Posted by Hallah_az

Using the short cut rule find the derivative of the following functions then simplify results. Please explain how you got it
m(x)=4x^3-15x^2+x-7
h(x)=(3x^2+7)(x^3-x)
g(x)=x
s(t)=4^t5+20t
Hello,

to1.:
$\frac{dm}{dx}=3 \cdot 4x^2-2 \cdot 15x+1=12x^2-30x+1$

to 2. You have to use the procuct rule:

$\frac{dh}{dx}=(x^3-x) \cdot 2 \cdot3x+(3x^2+7)(3 \cdot x^2-1)=15x^4+12x^2-7$

to 3.:
$\frac{dg}{dx}=1$

to 4.: (I assume that you made a mistake in typing the equation)
$\frac{ds}{dx}=5 \cdot 4t^4+20=20(t^4+1)$

Greetings

EB