# Are Trig Functions Always Positive?

All the trig functions are positive in Quadrant 1. Sine and cosecant are positive in Quadrant 2, tangent and cotangent are positive in Quadrant 3, and cosine and secant are positive in Quadrant 4.

## Can you have a negative sine function?

Different values of a

The original sine curve is represented by the gray line. … The difference with a negative value of a however, is our sine curve now has a negative amplitude. In other words, our graphs are the same as when a was a positive value, but are now reflected across the x-axis.

## Why am I getting a negative sine?

Both x and y coordinates are negative in the third quadrant. Since the hypotenuse is a +1, both the sine and the cosine must be negative. As the angle increases from 180° to 270°, the sine increases in magnitude but is now negative, so, the sine decreases from 0 to -1.

## What is negative sine equal to?

The negative angle identities also tell us the symmetries of the cosine and sine functions. A function f is even if f(-x) = f(x) for every x in the domain of f. Since cos(-θ) = cos θ, we conclude that cosine is an even function. … Since sin(-θ) = – sin θ, we conclude that sine is an odd function.

### Are Hypotenuses negative?

When we do this, all the hypotenuses have length one; we don’t get any negative hypotenuse lengths. But the legs point left and right, up and down. They are actually the coordinates of the point on the unit circle through which passes the terminal ray of the angle in standard position.

### Is Tan positive or negative?

This can be summed up as follows: In the fourth quadrant, Cos is positive, in the first, All are positive, in the second, Sin is positive and in the third quadrant, Tan is positive. This is easy to remember, since it spells “cast”.

### Can the hypotenuse be negative in trigonometry?

For each of the six trigonometric functions, identify the quadrants where they are positive and the quadrants where they are negative. … Thus all 6 trigonometric functions are positive. In quadrant II the hypotenuse and opposite sides are positive and the adjacent side is negative.

### What happens when an angle is negative?

Same distance, different directions. a positive angle starts from an initial side and moves clockwise to its terminal side. A negative angle starts from an initial side and moves counterclockwise to its terminal side.

### Is there a negative angle?

Angle measure can be positive or negative, depending on the direction of rotation. … Positive angles (Figure a) result from counterclockwise rotation, and negative angles (Figure b) result from clockwise rotation. An angle with its initial side on the x‐axis is said to be in standard position.

### How do you get a negative sin?

Inverse Sine Function

2. sin a° = 18.88/30.
3. Calculate 18.88/30:sin a° = 0.6293…
4. Inverse Sine:a° = sin1(0.6293…)
5. Use a calculator to find sin1(0.6293… ):a° = 39.0° (to 1 decimal place)

### What is a 45 degree triangle called?

For example, a right triangle may have angles that form simple relationships, such as 45°–45°–90°. This is called an “angle-based” right triangle. A “side-based” right triangle is one in which the lengths of the sides form ratios of whole numbers, such as 3 : 4 : 5, or of other special numbers such as the golden ratio.

### Why can a hypotenuse be negative?

Because it is the length of the side of a triangle and lengths cannot be negative.

### Is the hypotenuse always the longest side?

The hypotenuse is always the longest side in a right triangle because it is opposite of the largest angle, the ninety degree angle.

### What is tan180 value?

FAQs on Tan 180 Degrees

Tan 180 degrees is the value of tangent trigonometric function for an angle equal to 180 degrees. The value of tan 180° is 0.

### What is tan equal to?

The tangent of x is defined to be its sine divided by its cosine: tan x = sin x cos x . … The secant of x is 1 divided by the cosine of x: sec x = 1 cos x , and the cosecant of x is defined to be 1 divided by the sine of x: csc x = 1 sin x .

### What quadrants is sine negative?

The sine ratio is y/r, and the hypotenuse r is always positive. So the sine will be negative when y is negative, which happens in the third and fourth quadrants.

### Which quadrants is tan negative?

Considering the other quadrants, we see a pattern. In Quadrant II, sin ⁡ θ displaystyle sin{theta} sinθ is positive, cos ⁡ θ displaystyle cos{theta} cosθ and tan ⁡ θ displaystyle tan{theta} tanθ are negative.

### What is reciprocal of sin?

The cosecant is the reciprocal of the sine. It is the ratio of the hypotenuse to the side opposite a given angle in a right triangle.

### What is Arctan formula?

In trigonometry, arctan is the inverse of the tangent function and is used to compute the angle measure from the tangent ratio (tan = opposite/adjacent) of a right triangle. Arctan can be calculated in terms of degrees and as well as radians. \$large arctan (x)=2arctan left ( frac{x}{1+sqrt{1+x^{2}}} right )\$

### What is tan90 value?

The exact value of tan 90 is infinity or undefined.

### What are the side lengths of a 45 45 90 triangle?

A 45°-45°-90° triangle is a special right triangle that has two 45-degree angles and one 90-degree angle. The side lengths of this triangle are in the ratio of; Side 1: Side 2: Hypotenuse = n: n: n√2 = 1:1: √2. The 45°-45°-90° right triangle is half of a square.