Ltn→∞∑n−1r=0nn2+r2 ⇒Ltn→∞∑n−1r=01n⎛⎜ ⎜ ⎜ ⎜⎝11+(r2n2)⎞⎟ ⎟ ⎟ ⎟⎠ We can write in the form of: Ltn→∞∑n−1r=01nf(rn)=∫10f(x)dx
f(rn)=11+(rn)2;f(x)=11+x2 ∫1011+x2dx=tan−1x|10=π4
The value of n∑r=0(−1)rnCrr+2 is equal to .