Answer:
x+30=90
OR
180-120=x
The measure of the angle is 60 degrees.
Step-by-step explanation:
Plug in 60 as x and it will fit each equation.
X = 18°
cos 54° = sin 36°
cos 3 x = sin 2 x
cos ( 2 x + x ) = sin 2 x
cos 2 x cos x - sin 2 x sin x = 2 sin x cos x
( cos² x - sin² x ) cos x - 2 sin² x cos x = 2 sin x cos x / : cos x
( divide both sides by cos x )
cos² x - sin² x - 2 sin² x = 2 sin x
1 - sin² x - 3 sin² x - 2 sin x = 0
- 4 sin² x - 2 sin x + 1 = 0 substitution: u = sin x
- 4 u² - 2 u + 1 = 0
u = 2 -√20 / - 4
sin 18° = (√ 5 - 1 )/4 
cos 18° = √( 1² - ((√5 - 1)/4)²
cos 18° = (10+2√5)^(1/2) / 4
The next number in the pattern would be 14.03.
To find this, note the differences found by subtracting each number from the number that comes after.
4.03 - 2.78 = 1.25
5.78 - 4.03 = 1.75
8.03 - 5.78 = 2.25
10.78 - 8.03 = 2.75
Since each difference goes up by .5 each time, we know we can add .5 to the last difference to find the newest one.
2.75 + .5 = 3.25
Now we have the difference, so we add that to the last number.
10.78 + 3.25 = 14.03
Answer:
its 3/10
Step-by-step explanation:
V = 3/10
3
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10