The easiest way to do this is to plot the points. I used the pythagorean theorem for this one, too. Add the side lengths to get the perimeter: 5 + 5 + 5 + 3 + √40 = 24.32455532 units or just 24 units.
Answer:
a) cos(α+β) ≈ 0.8784
b) sin(β -α) ≈ -0.2724
Step-by-step explanation:
There are a couple of ways to go at these. One is to use the sum and difference formulas for the cosine and sine functions. To do that, you need to find the sine for the angle whose cosine is given, and vice versa.
Another approach is to use the inverse trig functions to find the angles α and β, then combine those angles and find find the desired function of the combination.
For the first problem, we'll do it the first way:
sin(α) = √(1 -cos²(α)) = √(1 -.926²) = √0.142524 ≈ 0.377524
cos(β) = √(1 -sin²(β)) = √(1 -.111²) ≈ 0.993820
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a) cos(α+β) = cos(α)cos(β) -sin(α)sin(β)
= 0.926×0.993820 -0.377524×0.111
cos(α+β) ≈ 0.8784
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b) sin(β -α) = sin(arcsin(0.111) -arccos(0.926)) ≈ sin(6.3730° -22.1804°)
= sin(-15.8074°)
sin(β -α) ≈ -0.2724
Y=4
3y/4=12/3
y=4 3/3=1
12/3=4 so y=4
If you were to solve this equation you would get answers of x=-2 and x=-8
Is it 22.5 b/c 22.5 *2 = 45 and 22.5 +22.5= 45. or do u mean both numbers have to be the same