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tandoorichicken
Dec11-03, 09:16 PM
I think Mr. Gishe went trigger happy when he was assigning homework today.

y=\sqrt{a^2-x^2} where -a<=x<=a is a semicircle with r=a
show why \int_{-a}^{a} \sqrt{a^2-x^2}\,dx = \frac{1}{2} \pi a^2

(I think that's how its written)

StephenPrivitera
Dec11-03, 11:32 PM
What does the integral represent if the integrand is positive!!??? AREA!!!!!!!
What's the area of a half circle?

himanshu121
Dec12-03, 02:14 AM
It is given in the que it is a semi-circle
Do you know the area of circle
if yes then u can find the area of semicircle

or if u dont know n u want to calulate the integral

substitute
x=asinz