Sin 2x - sin x=0
Using the trigonometric identity: sin 2x=2 sinx cosx
2 sinx cosx - sinx =0
Common factor sinx
sinx ( 2 cosx -1)=0
Two options:
1) sinx=0
on the interval [0,2π), the sinx=0 for x=0 and x=<span>π=3.1416→x=3.14
2) 2 cosx - 1=0
Solving for cosx
2 cosx-1+1=0+1
2 cosx = 1
Dividing by 2 both sides of the equation:
(2 cosx)/2=1/2
cosx=1/2
cosx is positive in first and fourth quadrant:
First quadrant cosx=1/2→x=cos^(-1) (1/2)→x=</span><span>π/3=3.1416/3→x=1.05
Fourth quadrant: x=</span>2π-π/3=(6π-π)/3→x=5<span>π/3=5(3.1416)/3→x=5.24
Answer: Solutions: x=0, 1.05, 3.14, and 5.24</span>
Answer:
Step-by-step explanation:
Method #1
We can draw a <em>right triangle</em> on the graph upon where the points are located and use the Pythagorean Theorem:
* Whenever we talk about distance, we ONLY want the NON-NEGATIVE root.
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Method #2
Or, we can use the Distance Formula:
![\sqrt{[-x_1 + x_2]^{2} + [-y_1 + y_2]^{2}} = D](https://tex.z-dn.net/?f=%5Csqrt%7B%5B-x_1%20%2B%20x_2%5D%5E%7B2%7D%20%2B%20%5B-y_1%20%2B%20y_2%5D%5E%7B2%7D%7D%20%3D%20D)
<em>B</em>[7, 10] <em>A</em>[13, 2]
![\sqrt{[-2 + 10]^{2} + [-13 + 7]^{2}} = D](https://tex.z-dn.net/?f=%5Csqrt%7B%5B-2%20%2B%2010%5D%5E%7B2%7D%20%2B%20%5B-13%20%2B%207%5D%5E%7B2%7D%7D%20%3D%20D)
![\sqrt{8^{2} + [-6]^{2}} = D](https://tex.z-dn.net/?f=%5Csqrt%7B8%5E%7B2%7D%20%2B%20%5B-6%5D%5E%7B2%7D%7D%20%3D%20D)
* Whenever we talk about distance, we ONLY want the NON-NEGATIVE root.
** You see? It does not matter which method you choose, as long as you are doing the work correctly.
I am delighted to assist you anytime.
Hey hey y’all is that the answer
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