Question
Mathematics Question on Integration by Parts
∫01(5xe2x−tan(π/4))dx=
(45)∗e2+41
(45)∗e2+49
(43)∗e2+41
(41)∗e2+45
(45)∗e2
(45)∗e2
Solution
The correct option is (E): (45)∗e2
Step 1:
Find the antiderivative of each term:
∫(5xe2x−tan(4π))dx
The antiderivative of 5xe2x with respect to x can be found using integration by parts.
Let's take t=5x and dt=e2xdx.
Then, dt=5dx and u=21e2x.
Using the integration by parts formula: ∫u dv = uv - ∫v du
We get: ∫(5xe2x)dx=(21)∗5x∗e2x−∫(21)e(2x)∗5dx
=25x∗e2x−25∫e2xdx
=25x∗e2x−25∗21e2x+C1
= 25x∗e2x−45e2x+C1
The antiderivative of tan(4π) with respect to x is simply -x since tan(4π) is a constant.
_Step 2: _
Apply the limits:
∫01(5xe2x−tan(π/4))dx
=[251e2∗1−45e2∗1+C1]−[0−C1]
=[25∗e2−45∗e2]+C1−(−C1)
=(25−45)∗e2=45∗e2
=(45)∗e2 (_Ans)