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
Step-by-step explanation:
Equation of straight line is y=mx+c
choose any two points on straight line
for me I choose:(-3,11) and (3,-1)
use these two points to find gradient,m.
m= (-1-11)/(3-(-3))
m= -2
now, y=-2x+c
choose any point on the straight line
I choose point (3,-1)
sub the point into the equation to find c
-1=-2(3)+c
c=5
equation: y=-2x+5
It would be to little because it would only be 30 cents
Answer:
50%
Step-by-step explanation:
TRUST
M = - 7 - 3 / - 2 - 4
m = - 10 / - 6
m = 10/6
m = 5/3
y = 5/3x + c , (4,3)
3 = 5/3(4) + c
12 = 20 + 4c
4c = - 8
c = - 2
y = 5/3x - 2
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