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3 years ago

State the intervals for which the given quadratic is positive and when it is negative.

Mathematics

1 answer:

goblinko [34]3 years ago

3 0

Answer:

Positive at (-9, 2)
Negative at ( -oo, -9) or (2, + oo)

Step-by-step explanation:

Given function

y= -2x^2 - 14x + 36

Getting zero's

-2x^2 - 14x + 36 = 0
x^2 + 7x - 18 = 0

x = ( -7 ± √(49 +72))/2 = ( -7 ± 11)/2
x = - 9 and x = 2

As the x^2 has negative coefficient, the function is positive between -9 and 2

- 9 < x < 2 or
(-9, 2)

And it is negative at:

x < -9 and
x > 2
or
( -oo, -9) or (2, + oo)

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2 years ago

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2 years ago

A lab is testing the amount of a certain active chemical compound in a particular drug that has been recently developed. The man

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Step-by-step explanation:

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Sample batches,

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= $Z(\frac{0.05}{2} )$

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