<span>the line over the 28 means the 28 repeats forever.
1.282828.... and so on
let x be the rational number 1.28...
we can use this trick:
100*1.282828....= 128.282828...
(the decimal 28 part repeats)
100x = 128.28...
next:
100x - x = 128.282828... - 1.282828...
the .282828... part will be subtracted away
99x = 127
divide both sides by 99 to get
x= 127/99</span>
Answer:
Answers!!!!!!
HOPE THIS HELPS!!!!!!!!!!
Step-by-step explanation:
If tan0=-3/4 and 0 is in quadrant IV, cos20= (33/25, -17/25, 32/25, 7/25, 24/25?) and tan20= (24/7, -24/7, 7/25, -7/25, 13/7, -1
Oksana_A [137]
Answer:
- cos(2θ) = 7/25
- tan(2θ) = -24/7
Step-by-step explanation:
Sometimes, it is easiest to let a calculator do the work. (See below)
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The magnitude of the tangent is less than 1, so the reference angle will be less than 45°. Then double the angle will be less than 90°, so will remain in the 4th quadrant, where the cosine is positive and the tangent is negative.
You can also use the identities ...
cos(2θ) = (1 -tan(θ)²)/(1 +tan(θ)²)
cos(2θ) = (1 -(-3/4)²)/(1 +(-3/4)²) = ((16-9)/16)/((16+9)/16)
cos(2θ) = 7/25
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tan(2θ) = 2tan(θ)/(1 -tan(θ)²) = 2(-3/4)/((16-9/16) = (-6/4)(16/7)
tan(2θ) = -24/7
Answer:
13.636
Step-by-step explanation:
The area can be found using Heron's formula:
A = √(s(s-a)(s-b)(s-c))
where s=(a+b+c)/2.
For the given triangle, ...
a=9, b=4, c=12, s=(9+4+12)/2 = 12.5
A = √(12.5(3.5)(8.5)(0.5)) = √185.9375 ≈ 13.636
The area of the triangle is about 13.636 square units.