# Question: What Is A Sin In Math?

## What is a sin and cos?

Sine and cosine — a.k.a., sin(θ) and cos(θ) — are functions revealing the shape of a right triangle.

Looking out from a vertex with angle θ, sin(θ) is the ratio of the opposite side to the hypotenuse , while cos(θ) is the ratio of the adjacent side to the hypotenuse ..

## What is sin a and sin B?

sin(A + B) = sinA cosB + cosA sinB sin(A − B) = sinA cosB − cosA sinB cos(A + B) = cosA cosB − sinA sinB cos(A − B) = cosA cosB + sinA sinB sin2 A + cos2 A = 1, sin 2A = 2 sinA cosA cos 2A = 2 cos2 A − 1=1 − 2 sin2 A 2 sinA cosB = sin(A + B) + sin(A − B)

## What does Sine mean?

In mathematics, the sine is a trigonometric function of an angle. The sine of an acute angle is defined in the context of a right triangle: for the specified angle, it is the ratio of the length of the side that is opposite that angle, to the length of the longest side of the triangle (the hypotenuse).

## Who invented trigonometry?

Trigonometry in the modern sense began with the Greeks. Hipparchus (c. 190–120 bce) was the first to construct a table of values for a trigonometric function.

## What does cosine mean?

noun. Trigonometry. (in a right triangle) the ratio of the side adjacent to a given angle to the hypotenuse. the sine of the complement of a given angle or arc. Abbreviation: cos.

## How do you find sin 10?

If you want to find the exact value. You can use the trigonometric identities by using Sin(a-b)=Sin(45–30) to get the value of Sin15 which you can assume to be 3x to find Sin5 which you can once more substitute in the Sin2x formula to get Sin10 which you AGAIN substitute in the Sin2x formula to get Sin20.

## How do you find the value of an angle?

HOW TO FIND VALUES OF TRIGONOMETRIC FUNCTIONS OF ANY ANGLEStep 1 : To find the value of any trigonometric angles, first we have to write the given angles in any one of the following forms. (90 + θ) … Step 2 : If we write the given angles in the form (90 + θ), (90 – θ), (270 + θ) or (270 – θ), we have to convert the given trigonometric ratios as follows. sin θ <---> cos θ

## How do you find the sine of an angle?

sin 75°: Now using the formula for the sine of the sum of 2 angles, sin(A + B) = sin A cos B + cos A sin B, we can find the sine of (45° + 30°) to give sine of 75 degrees.

## How do you calculate sin by hand?

Make sure the angle is between -Pi and Pi. Because sine is a periodic function, with period 2*Pi, just subtract or add 2*Pi enough times to get the angle between those two points. Now, we’re ready to go: sin(x) = x – x^3/3!

## How do you convert sin to degrees without a calculator?

If sin(theta) = x, theta = arcsin(x) = approx x + (1/6) x^3+ (3/40) x^5 + (5/112) x^7 + (35/1152) x^9. Then you will have to change to degrees by multiplying by 180 / pi. Doing all that arithmetic by hand (which would be without a calculator) ?

## What is sin b equal to?

The opposite over the main hypotenuse (7) is sin B. Since the side marked “opposite” (7) is in both the numerator and denominator when cos A and sin B are multiplied together, cos A sin B is the top part of the original opposite — for (A + B) — divided by the main hypotenuse (8).

## What is the formula for sin a sin B?

sin A sin B = ½ cos(A − B) − ½ cos(A + B)

## What are the 6 basic trigonometric functions?

There are six trigonometric ratios, sine, cosine, tangent, cosecant, secant and cotangent.