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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I believe it's $2250 since you just subtract.

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3 years ago

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She should invest $6491.73.

The equation we use to solve this is in the form
$A=p(1+\frac{r}{n})^{nt}$ ,
where A is the total amount in the account, p is the principal invested, r is the interest rate as a decimal, n is the number of times per year the interest is compounded, and t is the amount of time.

A in our problem is 14000.
p is unknown.
r is 6% = 6/100 = 0.06.
n is 2, since it is compounded semiannually.
t is 13.

$14000=p(1+\frac{0.06}{2})^{13*2}
\\
\\14000=p(1+0.03)^{26}
\\
\\14000=p(1.03)^{26}
\\
\\\text{Dividing both sides by }1.03^{26}\text{, we have}
\\
\\\frac{14000}{1.03^{26}}=\frac{p(1.03)^{26}}{1.03^{26}}
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why is using the metric system superior to using the standard system of measurement... Please someone help I need this and I tri

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Metric is used world-wide and is used everywhere except in english places (britan and USA)

some examples why metric is nice

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0 C⁰=freezing tempurature
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