Hi,

Use \left( and \right) in place of ( and ), respectively. This way LaTeX will choose the size of the brackets. The following code

givesCode:\left( \sqrt[1^0]{\frac{{\sqrt{\frac{198(99^3(99^{-1}))}{99}}}}{\sqrt {2}}} \right)^{sin90\cdot^{cos90\cdot^{tan45\cdot}}}

Edit:\log_{10}24 gives .Whilst I'm here, how do you get logx n