# What is the equation of the line normal to #f(x)=(2x^2 + 1) / x# at #x=-1#?

##### 1 Answer

The normal line is given by

#### Explanation:

Rewrite

Then, using the power rule,

When

Also, when

If we have the slope to the tangent

Therefore, we know that the normal line is of the form

We know that the normal line passes through

Substitute

You can verify this on a graph:

graph{(y-(2x^2+1)/x)(y+x+4)((y+3)^2+(x+1)^2-0.01)=0 [-10, 10, -5, 5]}