How do you evaluate the definite integral u2u from [1,4]?

2 Answers
Jun 8, 2018

ϕ=41u2udu=23

Explanation:

Let,
ϕ=41u2udu

u=t2 du=2tdt

When, u=1t=1 and u=4t=2

ϕ=21t22t2tdt

ϕ=221t22dt

ϕ=2[t332t]21

ϕ=2[83413+2]

ϕ=2[732]

ϕ=2[13]

ϕ=23

ϕ=41u2udu=23

Jun 8, 2018

I=41u2udu=23

Explanation:

Here,

I=41u2udu

=41[uu2u]du

=41[u2u]du

=41[u122u12]du

=[u12+112+12×u12+112+1]41

=[u32322×u1212]41

=(4)32322×(4)1212(1)32322×(1)1212

=[(2)3322×212][1322×112]

=[23×88][234]

=163823+4

=1434

=23