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3 years ago

Which equations are correct? Select each correct answer.

Mathematics

2 answers:

Step2247 [10]3 years ago

7 0

Answer:

Option 2 and 3

Step-by-step explanation:

We know that as per distributive law, we have $a(b+c)=ab+ac$ .

Option 1.

$-5x^3(3x^3+2)=-15x^6-10x^3\neq -15x^9-10x^3$

So, option 1 is not correct.

Option 2.

$-2c^6(5c^3+6)=-10c^9-12c^6$

So, option 2 is correct.

Option 3.

$-3y^5(2y^3+3)=-6y^8-9y^5$

So, option 3 is correct.

Option 4.

$-4b^4(5b^2+6)=-20b^6-24b^4\neq -20b^8-24b^3$

So, option 4 is not correct.

Juliette [100K]3 years ago

3 0

Answer:

Equations 2 and 3 are correct

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4 years ago

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Answer:

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Step-by-step explanation:

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Where t follows a t distribution with $n_1+n_2 -2$ degrees of freedom and the pooled variance $S^2_p$ is given by this formula:

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Null hypothesis: $\mu_1 = \mu_2$

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