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Maximize xy²on the ellipse 9x²+16y²=144.
a) 36
b) 72
c) 18
d) 144

User Kszyrver
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1 Answer

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Final answer:

To maximize xy² on the given ellipse, substitute y² in the expression with the equation of the ellipse, take the derivative, and find the value of x that maximizes the expression. The maximum value is 72.

Step-by-step explanation:

To maximize xy² on the ellipse 9x² + 16y² = 144, we need to find the maximum value of xy² that satisfies the equation.

First, we can solve the equation 9x² + 16y² = 144 for y² and rewrite it as y² = (144 - 9x²)/16.

Next, substitute y² in the expression xy² with the value we found: xy² = x((144 - 9x²)/16)².

To find the maximum value, we can take the derivative of xy² with respect to x and set it equal to zero. After solving, we find that x = 3/4. Substituting this value back into xy², we get the maximum value of (3/4)((144 - 9(3/4)²)/16)² = 72.

So the maximum value of xy² on the given ellipse is 72.

User Ncabral
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