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2 years ago

Let $x$ be the positive number such that $2x^2 = 4x + 9.$

Mathematics

1 answer:

loris [4]2 years ago

4 0

Solve for x. I'll do it by completing the square:

2x² = 4x + 9

2x² - 4x = 9

x² - 2x = 9/2

x² - 2x + 1 = 11/2

(x - 1)² = 11/2

x - 1 = ± √(11/2)

x = 1 ± √(11/2)

x = 1 ± √22/2

x = (2 ± √22)/2

Take the solution with the positive square root. Then it follows that a = c = 2 and b = 22. So a + b + c = 26.

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1+2+3+4+5+6.......+99 what is the quickest way to find the answer Thank u

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Answer:

Step-by-step explanation:

Use the formula Sum = (a + L)*n/2

The tricky part is n. That's the number of terms between 1 and 99 inclusive.

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a)0.2240

b)0.5768

Step-by-step explanation:

Given:

µ=3

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$f_k=\frac{\mu^ke^-^\mu}{k!}$

a) Evaluating at k=3

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b)Evaluating at k=0,1,2:

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