Question

Any help? :)

Answer 1

any guesses? it is -13 because you are going the other way

Answer 2

Yeah, \[\int_a^bf(x)dx =-\int_b^a f(x)dx\]

Answer 3

if you want a better explanation than "going the other way" it is because \(\Delta x\) is \(\frac{b-a}{n}\) for a partition
so the first one has \(\frac{8-4}{n}\) and the second has \(\frac{4-8}{n}\) the negative of the first one

Answer 4

so n would be ?

Answer 5

the integral is the limit of the sum as \(n\to \infty\)

Answer 6

ok ok