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4 years ago

8

Suppose that the functions and are defined for all real numbers as follows. r(x)=3x^(2) s(x)=2x write the expressions for (r-s)(

x) and (r+s)(x) and evaluate (r*s)(-1).

1 answer:

nirvana33 [79]4 years ago

7 0

The expression for (r-s)(x) is found by subtracting s from r. That difference is $3 x^{2} -2x$ . The expression for (r+s)(x) is found by adding them, which is $3 x^{2} +2x$ . Now we are told to evaluate (r*s)(x) which means they want us to multiply those and state the "new" expression that results. $(3 x^{2} )(2x)=6x^3$ . There you go!

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Step-by-step explanation:

first, we need to find the slope

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now sub

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3 years ago

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$p \sim N(p,\sqrt{\frac{p(1-p)}{n}})$

The confidence interval for the difference of two proportions would be given by this formula

$(\hat p_1 -\hat p_2) \pm z_{\alpha/2} \sqrt{\frac{\hat p_1(1-\hat p_1)}{n_1} +\frac{\hat p_2 (1-\hat p_2)}{n_2}}$

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So we can find it like this:

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"=1-NORM.DIST(2.326,0,1,TRUE)"

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