Please help me with this problem.

Mathematics

1 answer:

MrRa [10]3 years ago

3 0

Step-by-step explanation:

$cos(x + 45 \degree) + cos(x - 45 \degree) = \sqrt{2} \\ cosx \: cos45 \degree - sinx \: sin45 \degree \\ + cosx \: cos45 \degree + sinx \: sin45 \degree = \sqrt{2} \\ 2cosx \: cos45 \degree = \sqrt{2} \\ 2cosx \times \frac{1}{ \sqrt{2} } = \sqrt{2} \\ 2cosx = \sqrt{2} \times \sqrt{2} \\ 2cosx = 2 \\ cosx = \frac{2}{2} \\ cosx = 1 \\ cosx = cos \: 0 \degree \\ \huge \red{ \boxed{ x = 0 \degree}} \\$

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The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

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This means that $p = 0.09$

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