80X3 PLUS 2x3 that is awnser
9514 1404 393
Answer:
A) 5x+12 = -12x-12
D) 5x+12 = -5x-12
Step-by-step explanation:
If you subtract the right side expression from both sides, you will get an equation with something equal to zero. If the 'something' has a variable in it, there is exactly one solution.
A: (5x+12) -(-12x-12) = 17x+24 = 0 . . . one solution
B: (5x+12) -(5x-5) = 17 = 0 . . . . no solutions
C: (5x+12)-(5x+12) = 0 = 0 . . . . infinite solutions
D: (5x+12) -(-5x-12) = 10x +24 = 0 . . . one solution
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
__
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
__
b) sin(β -α) = sin(arcsin(0.111) -arccos(0.926)) ≈ sin(6.3730° -22.1804°)
= sin(-15.8074°)
sin(β -α) ≈ -0.2724
