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3 years ago

Evaluate -3x³-4x for x=-1

Mathematics

2 answers:

anyanavicka [17]3 years ago

4 0

Answer:

Step-by-step explanation:

Sub -1 in for each x:

-3x³-4x

-3(-1)³-4(-1)

-3(-1)+4

3+4

murzikaleks [220]3 years ago

3 0

The answer is to your question is 7

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A new medical test provides a false positive result for hepatitis 2% of the time that is a perfectly healthy subject being teste

Oxana [17]

Given that X be the number of subjects who test positive for the disease out of the 30 healthy subjects used for the test.

The probability of success, i.e. the probability that a healthy subject tests positive is given as 2% = 0.02

Part A:

The probability that all 30 subjects will appropriately test as not being infected, that is the probability that none of the healthy subjects will test positive is given by:

 $P(X)={ ^nC_xp^x(1-p)^{n-x}} \\ \\ P(0)={ ^{30}C_0(0.02)^0(1-0.02)^{30-0}} \\ \\ =1(1)(0.98)^{30}=0.5455$


Part B:

The mean of a binomial distribution is given by

 $\mu=np \\ \\ =30(0.02) \\ \\ =0.6$

The standard deviation is given by:

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Part C:

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5 0

3 years ago

Can anybody help this question?

Oxana [17]

Answer:

the first option

Step-by-step explanation:

really, just look at the table.

is the mean value (10.4) larger than the median (13.4) ?

I hope you can see right away that it is not.

and you can see they are not the same either.

so, all the answer options mentioning mean larger than median or equal to median can be ruled out right away.

so, it is between the first two options.

now think ! how do we draw number lines ? a coordinate axis ?

the smaller numbers left, the larger numbers right. the numbers grow from left to right.

the mean value is simply the sum of all measurements divided by the number of measurements (how many median were done). if that is smaller that the median (so, the Mean is left of the Median), it means that the majority of measurements had a result smaller (to the left) than the Median. so, it is skewed-left.

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3 years ago

Given the function f(x) = 2x, find the value of f−1(32).

sergeinik [125]

Answer:

find the inverse

exchange x for y and y for x

y=2x

then

x=2y---------> clear y

y=x/2

f−1(x)=x/2

for x=32

f−1(32)=32/2----------> 16

the answer is 16

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3 years ago

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vfiekz [6]

Answer:

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Step-by-step explanation:

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3 years ago

Evaluate -3x³-4x for x=-1​

Evaluate -3x³-4x for x=-1