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2 years ago

Why is sin(20) = sin(160) = -sin(200) = -sin(340)?

Mathematics

2 answers:

stepladder [879]2 years ago

8 0

Answer:

see.

Step-by-step explanation:

The value of sin is the same at the same distance from the cuadrant limit of the point. For the case of 20°, we have that the sin is the same in the following case:

As 20 is positive we use the limit cuadrant at 90°. The distance of 20 to 90 is 70. So, sin(20)=sin(90+70)=sin(160).

Also we have that sin(x) is a odd function, so sin(-x)=-sin(x), so

sin(-20°)= -sin(20°)

-sin(-20°)=sin(20°)

-sin(340°)=sin(20°).

and,

sin(-160°)=-sin(160°)

-sin(-160°)=sin(160°)

-sin(200°)=sin(160°)=sin(20°).

AveGali [126]2 years ago

6 0

Because they're all the same distance from the x axis on a coordinate plane. Also, remember that in quadrant I, all trig values are positive. In Q II, only sine and cosecant are positive. In Q III, only tangent and cotangent are positive. In Q IV, only cosine and secant are positive. Think of it as All Students Take Calculus.

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Answer:

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Step-by-step explanation:

Information given

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X=52 represent the workers belonged to unions

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$p_o=0.113$ is the value that we want to test

$\alpha=0.05$ represent the significance level

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$p_v$ represent the p value

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Alternative hypothesis: $p > 0.113$

Part b

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Replacing we got:

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