How to find dx when given transformation?

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Can someone please explain to me how to do question 20? Thanks!

1 Answer
Jun 1, 2018

See below

Explanation:

int_(-3)^0 \ y' \ dx'

= int_(+3)^0 3y + 5 \ (-dx)

= int_(bb 0)^(bb 3) 3y + 5 \ bb (dx)

= 3 int_(0)^3 y \ dx + int_0^3 5 \ dx

= 3 (5) + (5x)_0^3 = 30