Sin(13π/8) , is in quadrant IV so the angle will be negative, find the reference angle.
<span>sin(13π/8) = -sin(16π/8 - 13π/8) = -sin(3π/8) = -cos(4π/8 - 3π/8) = - cos(π/8). </span>
<span>Use half angle formula for cos(x): </span>
<span>cos²(x/2) = (cos(x) + 1) / 2 </span>
<span>Let x = π/4 </span>
<span>cos²(π/8) = (cos(π/4) + 1) / 2 </span>
<span>cos²(π/8) = (√(2) / 2 + 1) / 2 </span>
<span>cos(π/8) = √(√(2) / 4 + 1/2) </span>
<span>-cos(π/8) = -√((√(2) + 2) / 4)</span>
Simple (Cross multiplication )
7 x
_ _ = 700/8 = 87.5 (100-87.5 = 12.5 is the missing value.
8 100
<span>Step 1: 0.04 = 4⁄100</span>
<span>Step 2: Simplify 4⁄100 = 1⁄25</span>
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Answer:
The perimeter of both figures is equal to 
Step-by-step explanation:
step 1
we know that
The perimeter of a square is equal to

where
b is the side length of the square
we have

substitute

step 2
we know that
The perimeter of a rectangle is equal to

we have


substitute

step 3
Equate both perimeters and solve for x




step 4
Find the perimeter of both
<em>square</em>

<em>rectangle</em>

Answer:
Should be P(A∩B)=P(A)⋅P(B)