If 5^√x + 12^√x = 13^√x, then x is equal to: 

If  $$\sqrt{a}+\sqrt{b}=15 \ and \ (\sqrt{a}-\sqrt{b} )=3$$ then the value of $$\sqrt{ab/4} $$ is 

What is the compound interest on a sum of ₹25,000 after three years at a rate of 12 per cent per annum interest compounded yearly?  

If x is real then the minimum value of (x²-x-1) is :

If $$x=(\sqrt2+1)^{1\over3} $$, the value of $$(x^3-{1\over {x^3}}) $$ is

If $$ {x^4}+{1\over{x^4}}$$ then find $$ {x^3}-{1\over{x^3}}=?$$

simplify the following equation
$$ (1-{1\over3})(1-{1\over4})(1-{1\over5})......(1-{1\over n})$$

If a^2x+2=1, where a is a positive real number other than 1, then x is equal to