Posted by **Anonymous** on Tuesday, February 8, 2011 at 10:05am.

find the indicated limits, if they exist.

1. lim (3x^3+x^2+1)/(x^3+1)

x-> -infinity

2. find the slope of the tangent line to the graph of the given function at any point:

f(x) = 2x +7

Could anyone please, please, please explain to me how to do these problems? It seems like sometimes I can do the problem and I think I know it but then I get another one wrong. I need to know what I'm messing up on.

- Calculus-Limits -
**MathMate**, Tuesday, February 8, 2011 at 10:13am
For a function composed of a rational function, the limit to infinity can be determined by the quotient of the leading terms of the numerator and denominator:

Lim 3x^3/x^3 x->∞

= Lim 3 x->∞

=3

The slope of the tangent to the (line) is the coefficient of x, namely 2.

In a general way, the tangent function is obtained by taking the derivative of the function, i.e. d(2x+7)/dx = 2.

## Answer this Question

## Related Questions

- Calculus - A piecewise function is given. Use the function to find the indicated...
- calculus - A piecewise function is given. Use the function to find the indicated...
- calculus - 1. Which of the following expressions is the definition of the ...
- calculus - To find the equation of a line, we need the slope of the line and a ...
- Calculus - 1. a) For the Function and point below , Find f’(a). b) Determine ...
- Calculus - 1. a) For the Function and point below , Find f’(a). b) Determine ...
- calculus - 8. Find the derivative of the function f(x) = cos^2(x) + tan^2(x) 9...
- Derivative Calculus - I just need my answers checked. 1) Find the derivative. f(...
- Calculus - Use the four-step process to find the slope of the tangent line to ...
- Calculus: for mathmate - Find the slope of the tangent line to the graph of the ...