The value of cos 2x is 119/169 after applying the trigonometric identity cos2x = 1 - 2sin²x option second is correct.
<h3>What is trigonometry?</h3>
Trigonometry is a branch of mathematics that deals with the relationship between sides and angles of a right-angle triangle.
We have given:
sinx = -5/13
and cosx > 0
We know,
cos2x = 1 - 2sin²x
sinx = -5/13
Squaring on both sides:
sin²x = 25/169
Multiply by 2 on both the sides:
2sin²x = 2(25/169)
Add -1 on both sides:
-1 + 2sin²x = -1 + 2(25/169)
or
1 - 2sin²x = 1 - 2(25/169)
cos2x = 1 - 50/169
cos2x = 119/169 (as the cosx > 0)
Thus, the value of cos 2x is 119/169 after applying the trigonometric identity cos2x = 1 - 2sin²x option second is correct.
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Answer:
15.8 meters
Step-by-step explanation:
We have the following information:
The length of the intercepted arc for the circle R = 103 * π meters
The arc length of circle S = 163 * π meters
We also know the radius of the circle R (10) but not that of the circle S (x).
We are told that circles R and S have a central angle that measures 60 °. Therefore, the radius of circle S to the radius of circle R is equal to the length of the intercepted arc S to the length of the arc R, thus:
Radius S / Radius R = Length S / Length R
I know all, except the radius of S, we organize for this value and we have:
Radius S = (Length S / Length R) * Radius R
Replacing:
Radius S = (163 * π / 103 * π) * 10
Radius S = 15,825 meters
So the radius of the circle S = 15.8 meters
Answer:
46.67 %
Step-by-step explanation:
Total thickness = 30
14 of this is concrete 14/30 x 100% = 46.67 %
Answer:1 is the numerator 13 is the denominator
Step-by-step explanation:
5/6 - x = 8/15
5/6 - 8/15 = x
25/30 - 16/30 = x
9/30 reduces to 3/10 = x <==Armand burned 3/10 of a row