given the slope of the curve at the points x=1,2,3
slope of the curve f(x)=f1(x)
f1(1)=1/root3, f1(2)=root3, f1(3)=1
let f1(x)=t
then f11(x)dx=dt
[ ]
[ ] f
1(x)f
11(x)dx=
[ ]
[ ] tdt within the limits 1to3
=t2/2 with in the limits 1 to 3
=1/2(1-1/3)=1/3
[ ]
[ ] dt=t with in the limits 2to 3
=1-root3
1/3+1-root3=4/3-root3
f1(x) is derivative of f(x)
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