(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Find the equation of the line tangent to y=(x²+3x)² (2x-2)³, when x=8

2. Relevant equations

3. The attempt at a solution

dy/dx = 56x^6+144x^5-240x^4-320x^3+504x^2-144x......or........8x(x+3)(x+2)(7x-3)(x-1)²

dy/dx (8) = 18282880

y(x) = 21249536

Equation of tangent line at x=8;

y= 18282880x - 125013504

The problem is that this is a calc 1 question, 2 months in. There seems to be an odd space between the (x²+3x)² and (2x-2)³. I think the teacher might forgot to put a + or a - in the problem. What do you all think?

If I use a minus, I get a perfect 5000 for y(8). Making the end equation

y=2168x-12344.

Am I doing something wrong?

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# Equation of tagent line when x is given, but not Y.

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