Deriving f(x)=(x^2+5x+2)^4 & Finding Tangent with y=160x+16

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f(x)=(x^(2)+5x+2)^(4)

f'(x)= 4(x^2 + 5x + 2)^3 (2x + 5)
= 8x + 20(x^2 + 5x + 2)^3

is this right

than my equation of the tangent turned out to be y=160x +16
 
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madeeeeee said:
f(x)=(x^(2)+5x+2)^(4)

f'(x)= 4(x^2 + 5x + 2)^3 (2x + 5)

Ok

= 8x + 20(x^2 + 5x + 2)^3
Not okay.
is this right

than my equation of the tangent turned out to be y=160x +16[/QUOTE]
 
Im sorry, i don't understand where i went wrong
 
can i leave it as f'(x)= 4(x^2 + 5x + 2)^3 (2x + 5)
 
madeeeeee said:
f'(x)= 4(x^2 + 5x + 2)^3 (2x + 5)
= 8x + 20(x^2 + 5x + 2)^3
is this right
Notice something missing in your expression? Do you really want to multiply only the 20 by (x2 + 5x + 2)3?

madeeeeee said:
than my equation of the tangent turned out to be y=160x +16
Where did you get this? Was there a point that was given?
 
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