Answer: A) none of the equations are identities
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Part 1
Plug in theta = 0
sin(theta+pi/2) - cos(theta+pi/6) = 2*cos(theta) - sin(theta)
sin(0+pi/2) - cos(0+pi/6) = 2*cos(0) - sin(0)
1 - sqrt(3)/2 = 2*1 - 0
0.13 = 2
which is a false equation
So we do not have an identity in equation 1.
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Part 2
Plug in theta = 0
sin(theta+pi/6) + cos(theta+pi/3) = (sqrt(2)/3)*sin(theta) + 2*cos(theta)
sin(0+pi/6) + cos(0+pi/3) = (sqrt(2)/3)*sin(0) + 2*cos(0)
1/2 + 1/2 = 0 + 2
1 = 2
which is also false
This is not an identity either.
Xy compares to pq and x compares to q
V = ⁴/₃π(3³) ÷ 2
V = ⁴/₃ (27)π ÷2
V = 36π ÷ 2
V = 18π cm³
Eighth note is half of a quarter note, a quarter of a half note and an eighth of a whole note.