# What is the cos θ?

The Cos theta or cos θ is the ratio of the adjacent side to the hypotenuse, where θ is one of the acute angles.

## What is cos theta1?

⇒ θ = 2nπ ± 0°, n ∈ Z, [Since, the general solution of cos θ = cos ∝ is given by θ = 2nπ ± ∝, n ∈ Z.] Hence, the general solution of cos θ = 1 is θ = 2nπ, n ∈ Z.

## Where does cos theta equal 0?

cos x = 0, when x = ±π/2, ±3π/2, ±5π/2, … It means that cos x vanishes when x is an odd multiple of π/2. So, cos x = 0 implies x = (2n + 1)π/2 , where n takes the value of any integer. For a triangle, ABC having the sides a, b, and c opposite the angles A, B, and C, the cosine law is defined.

## What’s the opposite of a sin?

The antonym of sin is good deed. Sin means an action that is against religious rules, so the antonym should be in accordance with religion. According to many dictionaries virtue is the antonym of vice. Because it’s referring to something moral rather being religious.

## What is value of cos?

The value of cos 1 degrees is 0.9998476. . .. Cos 1 degrees in radians is written as cos (1° × π/180°), i.e., cos (0.017453. . .). In this article, we will discuss the methods to find the value of cos 1 degrees with examples.

## What does it mean if cos theta 0?

Let O be the centre of a unit circle. We know that in unit circle, the length of the circumference is 2π. cos θ = 0. If we started from A and moves in anticlockwise direction then at the points A, B, A’, B’ and A, the arc length travelled are 0, π2, π, 3π2, and 2π. Therefore, from the above unit circle it is clear that.

## What does it mean when cos theta 0?

Cornell University. The tangent identity is tan(theta)=sin(theta)/cos(theta), which means that whenever sin(theta)=0, tan(theta)=0, and whenever cos(theta)=0, tan(theta) is undefined (dividing by zero). When the tangent function is zero, it crosses the x-axis.

## Does Sohcahtoa work for all triangles?

Q: Is sohcahtoa only for right triangles? A: Yes, it only applies to right triangles. A: They hypotenuse of a right triangle is always opposite the 90 degree angle, and is the longest side.

## Can Cos equal 1?

1 Expert Answer 1) In the unit circle the x represent the cosine of the function and the y represent the sine of the trigonometric function. 2) Looking at the unit circle I noticed that cos(x) =1, corresponds to 360°. in other words cos (360º) =1, the answer is x=360º or x=2π radians.

## What is the value of cos theta =- 1?

The exact value of arccos(−1) is π . The cosine function is negative in the second and third quadrants.

## What is the COS formula?

The cosine formulas talk about the cosine (cos) function. Then the cosine formula is, cos x = (adjacent side) / (hypotenuse), where “adjacent side” is the side adjacent to the angle x, and “hypotenuse” is the longest side (the side opposite to the right angle) of the triangle.

## In what quadrant does lies if cos 0 and tan 0?

Therefore: In Quadrant I, cos(θ) > 0, sin(θ) > 0 and tan(θ) > 0 (All positive). For an angle in the second quadrant the point P has negative x coordinate and positive y coordinate.

## Which quadrant does θ lie if cot θ 0 and sin θ 0?

cot θ > 0, so tan θ >0 ie tan θ is positive. cos θ > 0 , ie cos θ is positive. ALL trig ratios are positive in the 1st quadrant. Hence,θ is in the 1st quadrant.

## How do you find cos315?

The value of cos 315 degrees can be calculated by constructing an angle of 315° with the x-axis, and then finding the coordinates of the corresponding point (0.7071, -0.7071) on the unit circle. The value of cos 315° is equal to the x-coordinate (0.7071). ∴ cos 315° = 0.7071.

## Who discovered Sohcahtoa?

It was Leonhard Euler who fully incorporated complex numbers into trigonometry. The works of the Scottish mathematicians James Gregory in the 17th century and Colin Maclaurin in the 18th century were influential in the development of trigonometric series.

## What is Sohcahtoa called?

“SOHCAHTOA” is a helpful mnemonic for remembering the definitions of the trigonometric functions sine, cosine, and tangent i.e., sine equals opposite over hypotenuse, cosine equals adjacent over hypotenuse, and tangent equals opposite over adjacent, (1) (2)

## Is hypotenuse only for right triangles?

Yes, the hypotenuse is always the longest side, but only for right angled triangles. For isosceles triangles, the two equal sides are known as the legs, while in an equilateral triangle all sides are known simply as sides.

## How do you use the sine and cosine rule?

The sine rule is used when we are given either a) two angles and one side, or b) two sides and a non-included angle. The cosine rule is used when we are given either a) three sides or b) two sides and the included angle.

## How do you find a hypotenuse?

The hypotenuse is termed as the longest side of a right-angled triangle. To find the longest side we use the hypotenuse formula that can be easily driven from the Pythagoras theorem, (Hypotenuse)2 = (Base)2 + (Altitude)2. Hypotenuse formula = √((base)2 + (height)2) (or) c = √(a2 + b2).

## When can you use sine law?

This law is useful for finding a missing angle when given an angle and two sides, or for finding a missing side when given two angles and one side.

## What cos2 45?

First of all, cos^2(45′) is the same thing as saying cos(45′)^2. Now we know from the unit circle that cos(45′)= rad2/2 (square root of 2 over 2), and when you do (rad2/2)^2, you get 2/4, or 1/2.