Answer:
- sin(2x) = -4/5
- cos(2x) = 3/5
- tan(2x) = -4/3
Step-by-step explanation:
It may be easiest to start with tan(2x).
tan(2x) = 2tan(x)/(1 -tan(x)²)
tan(2x) = 2(-1/2)/(1 -(-1/2)²) = -1/(3/4)
tan(2x) = -4/3 . . . . . still a 4th-quadrant angle
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Then cosine can be found from ...
cos(2x) = 1/√(tan(2x)² +1) = 1/√((-4/3)²+1) = √(9/25)
cos(2x) = 3/5
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Sine can be found from these two:
sin(2x) = cos(2x)tan(2x) = (3/5)(-4/3)
sin(2x) = -4/5
Answer:
90 = 150 of 60
88 = 220 of 40
75 = 300 of 25
100 = 125 of 80
Step-by-step explanation:
Answer:
5.23
Step-by-step explanation:
9514 1404 393
Answer:
f(x) = 4·3^x
Step-by-step explanation:
We assume the function will be of the form ...
f(x) = a·b^x
Substituting the given values, we can find 'a' and 'b'.
4/9 = a·b^(-2)
108 = a·b^3
Dividing the second equation by the first gives ...
108/(4/9) = b^(3 -(-2))
243 = b^5
b = 3 . . . . . . 5th root
Using the second equation, we can find 'a':
108 = a·3^3 = 27a
a = 108/27 = 4
The formula for the exponential function is ...
f(x) = 4·3^x
