2x + 1.5x +20 = 90
3.5 x = 90-20
3.5 x = 70
x = 70/3.5
x = 20
angle DAE = 2*20 = 40
angle CAD = 1.5*20 +20 = 50
T = 2 π / | 4/7 |
T = 2 π / 4/7
T = 2 π × 7 / 4
T = 7 π / 2
Thus the correct answer is option A .
It comes from integrating by parts twice. Let

Recall the IBP formula,

Let


Then

Apply IBP once more, with


Notice that the ∫ v du term contains the original integral, so that




Answer:
look at the picture i have sent