Friday

October 31, 2014

October 31, 2014

Posted by **Sarah** on Wednesday, March 10, 2010 at 7:20pm.

- Calculus -
**Damon**, Wednesday, March 10, 2010 at 7:27pmFind constants a,b and c such that the graph of f(x)=x^3+ax^2+bx+c will increase to the point (-3,18), decrease to the point (1,-14) and then continue increasing.

==============================

The derivative is zero at x = -3 and x = 1

f' = 3 x^2 + 2ax + b

0 = 3(9) +2a(-3) +b = 27-6a+b

and

0 = 3(1) +2a(1) +b = 3 +2a+b

so solve those two equations for a and b

then use the value of y = -1 at x = 1 to get c

- Calculus -
**Sarah**, Wednesday, March 10, 2010 at 7:45pmThank you Damon, but I still do not understand.

How do I solve for a, if I rearrange 27-6a+b in terms of a, I get a= 27+b/6.

But what do I plug in for b?

**Answer this Question**

**Related Questions**

Calculus - Find constants a,b, and c such that the function f(x)=ax^3+bx^2+c ...

7th grade math Ms. Sue please - 1. The price of a radio changes from $40.00 to $...

calculus - let f be the function f(x) = x^3 + 3x^2 - x + 2 a. the tangent to the...

Calculus - There is a point (P) on the graph of [x^2+y^2- 136 x + 12 y + 4560 = ...

Calculus - There is a point (P) on the graph of [x^2+y^2- 136 x + 12 y + 4560 = ...

chemistry- can you check my answers? - can you please check my answers?? 9. For ...

CHM - As the number of solute particles in a given volume of solution increase ...

Calculus (Urgent Help) - Okay, I need major help! Can someone tell me if these ...

Calculus - Functions? - #1. A cubic polynomial function f is defined by f(x) = ...

calculus - A curve passes through the point (1,-11) and it's gradient at any ...