Eric Nicholas K's answer to chien's Secondary 4 A Maths Singapore question.

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Eric Nicholas K
Eric Nicholas K's answer
5997 answers (Tutor Details)
1st
The second one is not easy. One thing we must recognise is that the definite integral of a curve below the x-axis will yield a negative value, so we must "modulus" this negative value to make the area under/over a graph positive.