A committee must be formed with 4 teachers and 5 students. If there are 11 teachers

Mathematics

1 answer:

Ivenika [448]1 year ago

7 0

Answer:

11C4 × 11C5

$\binom{11}{4} \times \binom{11}{5} = \frac{11 \times 10 \times 9 \times 8}{4 \times 3 \times 2 \times 1} \times \frac{11 \times 10 \times 9 \times 8 \times 7}{5 \times 4 \times 3 \times 2 \times 1} = 330 \times 462 = 152460$

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Rewrite 9cos 4x in terms of cos x.

rosijanka [135]

$\bf \qquad \textit{Quad identities}\\\\
sin(4\theta )=
\begin{cases}
8sin(\theta )cos^3(\theta )-4sin(\theta )cos(\theta )\\
4sin(\theta )cos(\theta )-8sin^3(\theta )cos(\theta )
\end{cases}
\\\\\\
cos(4\theta)=8cos^4(\theta )-8cos^2(\theta )+1\\\\
-------------------------------\\\\
9cos(4x)\implies 9[8cos^4(x)-8cos^2(x)+1]
\\\\\\
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as far as the previous one on the 2tan(3x)

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2 years ago

Find an equation for the perpendicular Bisector of the line segment whose endpoints are (-9,-8) and (7,-4

Alina [70]

equation for the perpendicular Bisector of the line segment whose endpoints are (-9,-8) and (7,-4)

Perpendicular bisector lies at the midpoint of a line

Lets find mid point of (-9,-8) and (7,-4)

midpoint formula is

$\frac{x_1+x_2}{2} ,\frac{y_1+y_2}{2}$