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What is the range of the function: h(x)=x+1/x^2 - 7x+10

User DarkRob
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Answer:

(-∞, -1-(2/3)√2] ∪ [-1+(2/3)√2, ∞)

Explanation:

To make it easier to differentiate, we'll rewrite the function as ...

h(x) = 2/(x-5) -1/(x-2)

Then the derivative is ...

h'(x) = -2/(x-5)^2 +1/(x-2)^2

This will be zero when ...

-2(x-2)^2 +(x-5)^2 = 0

-2(x^2 -4x +4) +(x^2 -10x +25) = 0

-x^2 -2x +17 = 0

x^2 +2x +1 = 17 +1

x +1 = ±√18 = ±3√2

x = -1 ±3√2

The values of the function at these locations are ...

h(-1-3√2) = -1 +(2/3)√2 ≈ -1.9428

h(-1+3√2) = -1 -(2/3)√2 ≈ -0.0572

Then the range of h(x) is ...

(-∞, -1-(2/3)√2] ∪ [-1+(2/3)√2, ∞)

What is the range of the function: h(x)=x+1/x^2 - 7x+10-example-1
User Khawar Ali
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