`1+1/(1+2)+1/(1+2+3)+1/(1+2+3+n)=(2n)/(n+1)`

a_ (n) = (1+ (1) / (n ^ (2))) (1+ (2 ^ (2)) / (n ^ (2))) ^ (2) (1+ (3 ^ ( 2)) / (n ^ (2))) ^ (3) ......... (1+ (n ^ (2)) / (n ^ (2))) ^ (n) then lim_ (n rarr oo) a_ (n) ^ (- (1) / (n ^ (2))) is equal to

Using the principle of mathematical induction prove that 1+(1)/(1+2)+(1)/(1+2+3)+(1)/(1+2+3+4)+...+(1)/(1+2+3+...+n)=(2n)/(n+1) for all n in N

lim_ (n rarr oo) [(1+ (1) / (n ^ (2)))) (1+ (2 ^ (2)) / (n ^ (2))) (1+ (3 ^ (2) ) / (n ^ (2))) ...... (1+ (n ^ (2)) / (n ^ (2)))] ^ ((1) / (n))

lim_ (n rarr oo) (1+ (1) / (2) + (1) / (2 ^ (2)) + (1) / (2 ^ (3)) + ...... (1) / (2 ^ (n))) / (1+ (1) / (3) + (1) / (3 ^ (2)) + (1) / (3 ^ (3)) ...... (1) / (3 ^ (n)))

For all quad prove that (1)/(1.2)+(1)/(2.3)+(1)/(3.4)+...+(1)/(n(n+1))=(n)/(n+1)

- (((n) / (1)) * ((1 + x) / (1 + nx)) + ((n (n-1)) / (1.2)) ((1 + 2x) / ((1 + nx) ^ (2))) - ((n (n-1) (n-2)) / (1.2.3)) ((1 + 3x) / ((1 + nx) ^ (3)))

The arithmetic mean of 1,2,3,...n is (a) (n+1)/(2) (b) (n-1)/(2) (c) (n)/(2)(d)(n)/(2)+1

(1)/(n)+(1)/(n+1)+(1)/(n+2)++(1)/(2n-1)=1-(1)/(2)+( 1)/(3)-(1)/(4)++(1)/(2n-1)