ShmoopTube

Where Monty Python meets your 10th grade teacher.

Search Thousands of Shmoop Videos


Solving trigonometric equations Videos 6 videos

ACT Math 5.1 Coordinate Geometry
212 Views

ACT Math: Coordinate Geometry Drill 5, Problem 1. Simplify the expression.

ACT Math 1.2 Trigonometry
274 Views

ACT Math Trigonometry Drill 1, Problem 2. Can you find the tangent?

ACT Math 1.4 Trigonometry
254 Views

ACT Math: Trigonometry Drill 1, Problem 4. Can you find the sine?

See All

ACT Math 1.4 Trigonometry 254 Views


Share It!


Description:

ACT Math: Trigonometry Drill 1, Problem 4. Can you find the sine?

Language:
English Language

Transcript

00:02

For a good time, solve this shmoopy question...

00:05

Find the sine of the quantity pi over 4?

00:08

And here are the potential answers...

00:12

I'll looks like instead of degrees we're getting into radians

00:16

the angle measure made by wrapping the radius length around a circle

00:20

Just think of pi as a 180 degrees. How did we come up with that?

00:24

Well the formula for the circumference of a circle is 2

00:28

pi times the radius of the circle.

00:31

Well in a unit circle, that's where the radius is just 1,

00:34

we can describe a full 360 degrees of a circle as 2pi

00:39

times one or just 2pi radians

00:43

if 360 degrees is 2pi radians...half of 360 is 180 or

00:48

pi radians. Plug in 180 for pi

00:51

in sine over pi over 4... 180 divided by four is 45

00:55

Sine of 45 degrees is the square root of 2 over 2.

01:00

Option D is our answer.

Related Videos

Inequalities in Number Lines
3229 Views

ACT Math: Coordinate Geometry Drill 1, Problem 1. Which inequality is expressed by the number line?

ACT Math 3.1 Intermediate Algebra
1955 Views

ACT Math: Intermediate Algebra: Drill 3, Problem 1. Find the fifth number in the series.

ACT Math 3.1 Plane Geometry
2559 Views

ACT Math: Plane Geometry Drill 3, Problem 1. What is the area of the trapezoid shape in the video?

Surface Area of Cylinders
14741 Views

Haven't you always wondered how much cardboard it takes to encase a trunk warmer for your pet elephant?

Perimeter of Irregular Shapes
4864 Views

Want to figure out the area and perimeter of irregular shapes? Break them down into regular shapes. For example, a flower can be broken down into s...