Slope of Tangent Line for f(x)=x^3+x at (2,10) | Algebraic Method

Mejiera
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Homework Statement




find the slope of the tangent line of f at the given point.

Homework Equations



f(x)= x^3 + x at (2,10)

The Attempt at a Solution


I know how to get the answer using the power rule, but I want to know the algebraic way of doing it
I get stuck at x^3 + x - 10/ x -2 how do I get rid of the x-2 in the bottom ?
 
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f'(x) is the instantaneous rate of change at any x on the graph of f(x). In other words, f'(x) is the exact slope at any point on the graph of f(x). First, take the derivative of f(x). Then from there you can evaluate for any x (in your case x=2) to find the slope of your tangent line.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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