Answer:
1.14200738982×10^26
Step-by-step explanation:
Substitution can make this integral much easier to evaluate.
<h3>Substitution</h3>
Let u = 7x² -x. Then du = (14x -1)dx. The limits on x become different limits for u:
for x = 1: u = 7(1²) -1 = 6
for x = 3: u = 7(3²) -3 = 60
<h3>Integral</h3>

Answer:
<h3>72 units</h3>
Step-by-step explanation:
Given D,E, and F are collinear points and E is between D and F, then the expression DE + EF = DF.... 1 is true
If DE is six times the length of EF, then;
DE = 6DF
DF = DE/6 .....2
Substitute equation 2 into 1;
DE + EF = DF
DE + DE/6 = DF
find the LCM
(6DE+DE)/6 = DF
cross multiply
6DE+DE = 6DF
7DE = 6DF
Given DF = 84units
7DE = 6(84)
7DE = 504
Divide both sides by 7
7DE/7 = 504/7
DE = 72
Hence the length of segment DE is 72units
4500 tons, which by the way is very unlikely