ShmoopTube
Where Monty Python meets your 10th grade teacher.
Search Thousands of Shmoop Videos
Right Triangles and Trigonometry Videos 37 videos
Verifying trig identities is important, especially when you're about to let one of them into the country—which is why they should keep their pass...
Mosquitos need their caffeine, just like the rest of us. Wouldn't think zipping around and stinging people all day long sap your energy?
Sine is the opposite over the hypotenuse; cosine is the adjacent over the hypotenuse; and tangent is the opposite side over the adjacent side....
ACT Math 1.4 Trigonometry 254 Views
Share It!
Description:
ACT Math: Trigonometry Drill 1, Problem 4. Can you find the sine?
- Trigonometry / Trig identities
- Trigonometry / SOHCAHTOA (values and properties of trig functions)
- Product Type / ACT Math
- Foreign Language / Arabic Subtitled
- Foreign Language / Korean Subtitled
- Foreign Language / Chinese Subtitled
- Foreign Language / Spanish Subtitled
- Functions / Extend the domain of trigonometric functions using the unit circle
- Functions / Extend the domain of trigonometric functions using the unit circle
- Trigonometry / Solving trigonometric equations
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
Full Transcript
- 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
ACT Math: Coordinate Geometry Drill 1, Problem 1. Which inequality is expressed by the number line?
ACT Math: Intermediate Algebra: Drill 3, Problem 1. Find the fifth number in the series.
ACT Math: Plane Geometry Drill 3, Problem 1. What is the area of the trapezoid shape in the video?
Haven't you always wondered how much cardboard it takes to encase a trunk warmer for your pet elephant?
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...