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Q: What is theta of a triangle?

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The cosine of theta is adjacent over hypotenuse, given a right triangle, theta not being the 90 degree angle, adjacent not being the hypotenuse, and theta being the angle between adjacent and hypotenuse. In a unit triangle, i.e. in a unit circle circumscribed with radius one, and theta and the center of the circle at the origin, cosine of theta is X.

Theta is just a Greek letter used to denote measurement of angle. Sine is a trigonometric function, i.e., the ratio of the side opposite to the angle theta to the hypotenuse of the triangle. So Sine theta means the value of sine function for angle theta, where theta is any angle.

Suppose triangle ABC is right angled at C. Suppose you are given that the angle at B is theta. Thenif you know the length of AB (the hypotenuse), thenBC = AB*cos(theta) andAC = AB*sin(theta)if you know the length of BC, thenAB = BC/cos(theta) andAC = BC*tan(theta)if you know the length of AC, thenAB= AC/sin(theta) andBC = AC/tan(theta)

SOH CAH TOA is a way of remembering what the functions sin, cos, & tan mean in a right angle triangle. With a triangle with one of the acute angles labelled (theta) the longest side H (Hypotenuse), the side opposite the labelled angle O, and the short side closest to the angle A (Adjacent) SOH ->SIN(Theta)=0/H CAH ->COS(Theta)=A/H TOA ->TAN(Theta)=O/A

If tan theta equals 2, then the sides of the triangle could be -2, -1, and square root of 5 (I used the Pythagorean Theorem to get this). From this, sec theta is negative square root of 5. It is negative because theta is in the third quadrant, where cosine, secant, sine, and cosecant are all negative.

Related questions

The answer depends on what theta represents!

when you have a right triangle and one of the two non-right angles is theta, sin(theta) is the side of the triangle opposite theta (the side not touching theta) divided by the side that does not touch the right angle

The sine theta of an angle (in a right triangle) is the side opposite of the angle divided by the hypotenuse.

In a Right Triangle SINE Theta is equal to the: (Length of opposite side) / (Length of Hypotenuse).

Tangent (theta) is defined as sine (theta) divided by cosine (theta). In a right triangle, it is also defined as opposite (Y) divided by adjacent (X).

The sine of an angle theta that is part of a right triangle, not the right angle, is the opposite side divided by the hypotenuse. As a result, you could determine the hypotenuse by dividing the opposite side by the sine (theta)...sine (theta) = opposite/hypotenusehypotenuse = opposite/sine (theta)...Except that this won't work when sine (theta) is zero, which it is when theta is a multiple of pi. In this case, of course, the right triangle degrades to a straight line, and the hypotenuse, so to speak, is the same as the adjacent side.

The cosine of theta is adjacent over hypotenuse, given a right triangle, theta not being the 90 degree angle, adjacent not being the hypotenuse, and theta being the angle between adjacent and hypotenuse. In a unit triangle, i.e. in a unit circle circumscribed with radius one, and theta and the center of the circle at the origin, cosine of theta is X.

Theta is just a Greek letter used to denote measurement of angle. Sine is a trigonometric function, i.e., the ratio of the side opposite to the angle theta to the hypotenuse of the triangle. So Sine theta means the value of sine function for angle theta, where theta is any angle.

If X and Y are sides of a right triangle, R is the hypoteneuse, and theta is the angle at the X-R vertex, then sin(theta) is Y / R and cosine(theta) is X / R. It follows, then, that X is R cosine(theta) and Y is R sin(theta)

You can use your trigonometric functions (sine, cosine, and tangent).

Suppose triangle ABC is right angled at C. Suppose you are given that the angle at B is theta. Thenif you know the length of AB (the hypotenuse), thenBC = AB*cos(theta) andAC = AB*sin(theta)if you know the length of BC, thenAB = BC/cos(theta) andAC = BC*tan(theta)if you know the length of AC, thenAB= AC/sin(theta) andBC = AC/tan(theta)

the formula for the arc of a triangle is the arc length is equal to the angle times the radius. s=arc length theta=angle made y length of the arc lenth r=radius s=theta times radius

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