Wednesday

July 30, 2014

July 30, 2014

Posted by **Larry** on Thursday, October 11, 2012 at 12:28am.

f(-3)=-3 and f'(-3)=2

find the coefficients a and b.

- Math -
**Reiny**, Thursday, October 11, 2012 at 8:49amf(x) = ax^2 + b

f ' (x) = 2ax

given :

f ' (-3) = 2 ----> 2a(-3) = 2

-3a = 1

a = -1/3 , so f(x) = (-1/3)x^2 + b

f(-3) = -3

---> (-1/3)(-3)^2 + b = -3

-3 + b = -3

b = 0

**so a = -1/3, b = 0 and f(x) = (-1/3)x^2**

check:

f(-3) = -(1/3)(9) = -3

f ' (x) = -(2/3)x

f '(-3) = -(2/3)(-3) = 2

all looks good.

**Related Questions**

chemistry - How many of the following are true concerning balanced chemical ...

chemistry - When the following combustion reaction is balanced using the ...

math - I will try it with x=20, y=15 From this, you can supply coefficients and ...

Math - 7) Use Pascal's Triangle to find the coefficients for (a + b)5 . I need ...

math - find the terms and leave the coefficients as factorials: Term with t^5 in...

math - find the terms and leave the coefficients as factorials. Term with b^8 in...

Chemistry - (1) Why are fractional coefficients permitted in a balanced ...

Math- Help Please - Find a polynominal of degree 4 that has integer coefficients...

math - In the binomial series from (a+b)^5, the powers of a decrease by 1 each ...

Math Algebra - Find a polynomial p(x) with real coefficients having the given ...