in a election about 500,000 people voted in all. what could be the exact number of people who voted in the election?

In ΔLMN, l = 8.7 cm, m = 2.3 cm and n=6.6 cm. Find the measure of ∠M to the nearest degree.

DIA [1.3K]

Answer:

7

Step-by-step explanation:

\underline{\text{Solution Method 2:}}

Solution Method 2:

Use original formula

a^2=b^2+c^2-2bc\cos A

a

2

=b

2

+c

2

−2bccosA

From reference sheet.

\text{Since we are finding }\angle M\text{,}

Since we are finding ∠M,

\text{plug in }2.3\text{ for side }a:

plug in 2.3 for side a:

Opposit the angle we want

2.3^2 = 6.6^2+8.7^2-2(6.6)(8.7)\cos M

2.3

2

=6.6

2

+8.7

2

−2(6.6)(8.7)cosM

Plug in values. Side "a" is opposite the wanted angle.

5.29 = 43.56+75.69-114.84\cos M

5.29=43.56+75.69−114.84cosM

Square sides.

5.29 =

5.29=

\,\,\color{white}{-} 119.25-114.84\cos M

−119.25−114.84cosM

Add.

-119.25=

−119.25=

\,\,-119.25

−119.25

-113.96=

−113.96=

\,\,-114.84\cos M

−114.84cosM

\frac{-113.96}{-114.84}=\cos M

−114.84

−113.96

=cosM

Divide to solve for cos(A).

M= \cos^{-1}(\frac{-113.96}{-114.84})\approx7.098\approx 7^{\circ}

M=cos

−1

(

−114.84

−113.96

)≈7.098≈7

∘

8 0

3 years ago

Read 2 more answers

Express the function y(t)= 4 sin 2πt + 15 cos 2πt in terms of (a) a sine term only. (b) Determine the amplitude, the period, the

Bond [772]

Answer:

See the step by step solution

Step-by-step explanation:

Consider a more general case of the form $a\sin(x)+b\cos(x)$ . We want to express it as a sine term only by using the following formula $\sin(\alpha+\beta) = \sin(\alpha)\cos(\beta)+\sin(\beta)\cos(\alpha)$

The trick consists on find a number $\beta \in [0,2\pi]$ such that $\cos(\beta) = a, \sin(\beta)=b$ . But, note that since $\cos^2(\beta)+\sen^2(\beta)=1$ it is most likely that $a^2+b^2neq 1$ . Then, we will use the following equations:

$\cos(\beta) =\frac{a}{\sqrt[]{a^2+b^2}=A,\sin(\beta) =\frac{b}{\sqrt[]{a^2+b^2}=B$

Then, problem turns out to be

$a\sin(x)+b\cos(x)= \sqrt[]{a^2+b^2}(A\sin(x)+B\cos(x)) =\sqrt[]{a^2+b^2}(\sin(x)\cos(\beta)+\sin(\beta)\cos(x))=\sqrt[]{a^2+b^2}\sin(x+\beta)$ ,

where $\beta = \tan^{-1}(\frac{B}{A})= \tan^{-1}(\frac{b}{a}). So, note that the frequency is the same. Then, a) Taking a=4 and b= 15 we have that 4 sin 2πt + 15 cos 2πt= [tex]\sqrt[]{15^2+4^2}\sin(2\pi t + \tan^{-1}\frac{15}{4})$

b) The amplitude is $\sqrt[]{15^2+4^2} = \sqrt[]{241}$ . Since $2\pi rad/s = 1 Hz$ the frequency is 1 Hz. The period is given by \frac{2\pi}{2\pi} = 1.