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3 years ago

Please help this question..

Mathematics

1 answer:

miskamm [114]3 years ago

7 0

Step-by-step explanation:

2).

Given that 1/(7+5√2)

We know that

The Rationalising factor of a+√b is a-√b

The denominator = 7+5√2

The Rationalising factor of 7+5√2 is 7-5√2

On Rationalising the denominator then

=> [1/(7+5√2)]×[ (7-5√2)/(7-5√2)]

=> [1×(7-5√2)]/(7+5√2)(7-5√2)]

=> (7-5√2)/[(7+5√2)(7-5√2)]

=> (7-5√2)/[7²-(5√2)²]

Since , (a+b)(a-b) = a²-b²

Where , a = 7 and b = 5√2

=> (7-5√2)/(49-50)

=> (7-5√2)/(-1)

=> -7+5√2

=> 5√2-7

3).

Given that (x-2)³

This is in the form of (a-b)³

Where, a = x and b = 2

We know that

(a-b)³ = a³-3a²b+3ab²-b³

=> (x-2)³ = x³-3(x²)(2)+3(x)(2)²-2³

=> (x-2)³ = x³-6x²+12x-8

The coefficient of x² is -6

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Answer:

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Step-by-step explanation:

Previous concepts and notation

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For this case since we have a right tailed test the p value is given by:

$p_v = P(\chi^2_{29}>42.963)=1-0.954=0.0459$

And the best option would be:

b. between .025 and .05

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4 years ago

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shepuryov [24]

Answer:

See below

Step-by-step explanation:

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