another question to bother this thread about is here
for who have C2 book its on page 193 Q 6 in the revision exercise 3 what I don't understand is that the book's answer is
4 and when I did integration of the two parts of my sketch , one area was -ve and other was +ve so I added them ignoring the -ve sign so...............are these steps right or I've just missed somethnig up
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cause my anwser was ''9.5''
Thanks in advance
