Hi everyone. Been looking at this question and have had no trouble integrating it however when asked to choose appropriate values for a and b I soon realised that I got a negative area and after looking at the mark scheme the integrals were different from what the question implied due to the integral of 1/x being present I think. I've attached both the graph and the question. Does anyone know why you change b to 2 and a to 1? Thanks! Please help ?
Changing the limits for an integral
- Thread starter alicekr
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Harry_the_cat
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The graph given is the graph of y=f(x). The graph of y=f(x-1) is this graph moved one unit to the right.
You are asked to use the integral of f(x-1) to find the area under y = f(x).
So the area under y = f(x) between x=0 and x=1 (as implied in the question) will be the same as the area under y = f(x-1) between x=1 and x=2.
Hence a=1 and b=2.