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3 years ago

Will mark brainliest !! Easy math

Mathematics

1 answer:

marshall27 [118]3 years ago

6 0

Answer:

increase = 37.38 cm²

You'd like the first way because it took less effort and less chance of a miscalculation.

Step-by-step explanation:

first way:

(just work with the difference in height)

(0.7 x 8.7 x 2) + (0.7 x 18 x 2) = 37.38 cm²

second way:

old total lateral surface area = (31 x 8.7 x 2) + (31 x 18 x 2) = 1655.4

new total lateral surface area = (31.7 x 8.7 x 2) + (31.7 x 18 x 2) = 1692.78

increase = 1692.78 - 1655.4 = 37.38 cm²

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a. Note that $f(x)=x^ne^{-2x}$ is continuous for all $x$ . If $f(x)$ attains a maximum at $x=3$ , then $f'(3) = 0$ . Compute the derivative of $f$ .

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To ensure that a maximum is reached for this value of $n$ , we need to check the sign of the second derivative at this critical point.

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Inflection points can occur where the second derivative vanishes.

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To decide which are actually inflection points, check the sign of $f''$ in each of the intervals $(-\infty,0)$ , $(0, 1)$ , $(1, 3)$ , and $(3,\infty)$ . It's enough to check the sign of any test value of $x$ from each interval.

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