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3 years ago

Cos²45+Sin²60 + sin^2 30

Mathematics

1 answer:

denpristay [2]3 years ago

4 0

Step-by-step explanation:

${ \cos}^{2} 45 \degree + { \sin}^{2} 60 + { \sin}^{2} 30 \degree \\ = \bigg( \frac{1}{ \sqrt{2} } \bigg)^{2} + \bigg( \frac{ \sqrt{3} }{ 2} \bigg)^{2} + \bigg( \frac{1}{2} \bigg)^{2} \\ \\ = \frac{1}{2} + \frac{3}{4} + \frac{1}{4} \\ \\ = \frac{2}{4} + \frac{3}{4} + \frac{1}{4} \\ \\ = \frac{2 + 3 + 1}{4} \\ \\ = \frac{6}{4} \\ \\ = \frac{3}{2} \\ \\ = 1 \frac{1}{2} \\$

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Answer:

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Step-by-step explanation:

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Answer:

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Step-by-step explanation:

1) Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

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