3 years ago

How many different combinations of two can be made from 80 people?

1 answer:

3 0

Plugging directly into the combination formula, the answer is $\binom{80}{2}=\frac{80!}{2!78!}=\frac{80\cdot 79}{2\cdot 1}=40\cdot 79=\boxed{3160},$ where we have cancelled out common factors.

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If f(x) = x^4-x^3+x^2 and g(x)= -x^2, where x does not = 0, what is (f/g)(x)?

Korvikt [17]

For this case we have the following functions:

$f (x) = x ^ 4-x ^ 3 x ^ 2\\g (x) = - x ^ 2$

By definition of composition of functions we have to: $(f \ g) (x) = \frac {f (x)} {g (x)}$

So:

$\frac {f (x)} {g (x)} = \frac {x ^ 4-x ^ 3 x ^ 2} {- x ^ 2} = \frac {x ^ 4} {- x ^ 2} +\frac {-x ^ 3} {- x ^ 2}+ \frac {x ^ 2} {- x ^ 2} =$

By definition of division of powers of the same base we have to place the same base and subtract the exponents:

$\frac {f (x)} {g (x)} = - x ^ 2+x-1$

ANswer:

$(\frac {f} {g}) (x) = - x ^ 2 +x-1$

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3 years ago

What is the slop of y=6x+3

GaryK [48]

The slope of y=6x+3 is 6

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3 years ago

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Work out the following questions

Basile [38]

Answer: The first one is 2 2/3 and the second one is 10 1/2

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3 years ago

Carlotta is making blue and orange necklaces in several lengths. For each necklace, her ratio of blue beads to orange beads is 3

agasfer [191]

5x=60
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3 years ago

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GREYUIT [131]

Answer:

0.65%, 9.2%, 40%, 656%

Step-by-step explanation:

see answer

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3 years ago