Find the value of `(1/2)^-2 + (1/3)^-2 + (1/4)^-2`

Find the value of (2^-1 xx 4^-1) :- 2^-2

Find the value of ( a^2 + sqrt(a^2 - 1))^4 + (a^2 - sqrt(a^2 - 1))^4 .

If 1/1^2+1/2^2+1/3^2+...oo=pi^2/6 then value of 1-1/2^2+1/3^2-1/4^2+...oo=

Find the value of tan { cot ^(-1) ((-2)/3)}

IF 25025 = p_(2)^(x1),p_(2)^(x2),p_(3)^(x3),p_(4)^(x4) find the values of p_(1), pz, p_(3), p_(4) and x_(1), x_(2), x_(3), x_(4) .

Find the principal value of cos^(-1) (-1/2)

Find value of (x+(1)/(x))^(3)+(x^(2)+(1)/(x^(2)))^(3)+"........"+(x^(n)+(1)/(x^(n)))^(3) .

Find the value of tan^(-1)[2cos(2"sin"^(-1)1/2)]

Evaluate (1(1)/(4))^2

Find the principal value for cos^(-1)(1/2)