Friday

November 21, 2014

November 21, 2014

Posted by **Dana** on Sunday, April 7, 2013 at 9:20pm.

- Calculus -
**Reiny**, Sunday, April 7, 2013 at 10:46pmlet the function be

y = ax^4 + bx^2 + c

since (0,10) is on it ----> c = 10

dy/dx = 4ax^3 + 2bx

at (3,253), dy/dx = 0

4a(27) + 2b(3) = 0

108a + 6b = 018a + b = 0

b = -18a

at (-3, 253) , dy/dx = 0

4a(-27) + 2b(-3) = 0 , this gives the same result, so nothing new here

but (3,253) lies on the actual curve

253 = 81a + 9b

sub in b = -18a

253 = 81a + 9(-18a)

253 = -81a

a = -253/81

then b = -18(-253/81) = 506/9

so**y = (-253/81)x^4 + (506/9)x^2 + 10**

check:

dy/dx = -1012/81x^3 + 1012x = 0 for a max/min

divide by -1012

x^3/81 - x = 0

times 81

x^3 - 81x = 0

x(x^2 - 9) = 0

x = 0 , or x = ±3

if x = 3 or -2

y = (-253/81)(81) + (506/9)(9)

= -253 + 506 =253 YEAHHH

(weird coefficients)

**Answer this Question**

**Related Questions**

Calc - Im not getting these answers at all, please help. Find a formula for the ...

calculus - Find a formula for the fourth degree polynomial p(x) whose graph is ...

calculus - fourth degree polynomial p(x) whose graph is symmetric about the y-...

Calculus - Find the equation of a quartic polynomial whose graph is symmetric ...

Pre-Calculus-check answers - The graph of the equation y=x^3-x is symmetric with...

College Algebra - 1.The graph of y = - 1/2 |x - 5| - 3 can be obtained from the ...

Math - Fundamental Theorem - We can actually use the Zeros Theorem and the ...

Pre-calculus - 1. The graph of the equation y = x2 – 3 is symmetric with respect...

Pre-calc - find a possible polynomial equation of degree 4 if the zeroes are -1,...

Algebra - Do I have this right? A first degree polynomial crosses the x axis A ...