Answer:
Step-by-step explanation:
∫(t = 2 to 3) t^3 dt
= (1/4)t^4 {for t = 2 to 3}
= 65/4.
----
∫(t = 2 to 3) t √(t - 2) dt
= ∫(u = 0 to 1) (u + 2) √u du, letting u = t - 2
= ∫(u = 0 to 1) (u^(3/2) + 2u^(1/2)) du
= [(2/5) u^(5/2) + (4/3) u^(3/2)] {for u = 0 to 1}
= 26/15.
----
For the k-entry, use integration by parts with
u = t, dv = sin(πt) dt
du = 1 dt, v = (-1/π) cos(πt).
So, ∫(t = 2 to 3) t sin(πt) dt
= (-1/π) t cos(πt) {for t = 2 to 3} - ∫(t = 2 to 3) (-1/π) cos(πt) dt
= (-1/π) (3 * -1 - 2 * 1) + [(1/π^2) sin(πt) {for t = 2 to 3}]
= 5/π + 0
= 5/π.
Therefore,
∫(t = 2 to 3) <t^3, t√(t - 2), t sin(πt)> dt = <65/4, 26/15, 5/π>.
Answer:
15 minutes
Step-by-step explanation:
Betty mows at 3 times the speed that Bullwinkle does, so is equivalent to having 3 Bullwinkles in her place. That makes the lawn get mowed as though 4 Bullwinkles were working, so it will take 1/4 the time it takes Bullwinkle to mow the whole yard. 1/4 of 60 minutes is 15 minutes.
Working together, Betty and Bullwinkle will take 15 minutes to mow the lawn.
The smallest one is -2/7
The largest one is 8/9 The difference between them is
8/9 - - 2/7 =
8/9 + 2/7 =
7*8/9*7 + 2*9/9*7 =
56 / 63 + 18 / 63 =
74 / 63 =
1 11/63
<span>Postulates are helpful because it helps you plan and solve geometry problems.
That's my guess. It doesn't tell me in the text either.</span>
