What is 3 to the power of the two times the square root of five

Hi MG,

I see that you have tried to use LaTex to write this - I am really pleased  

This was your attempt :)

$$3^2*sqrt(5)$$

sqrt is a function,  there are many functions in LaTex.

The trick is that the function must be preceded by a backwards slash.  \

now 5 is the "argument" of the function.  It must be in curly backets, the real name is parentheses  {}

so    sqrt(5) needs to be written as  \sqrt{5}

$$\sqrt{5}$$       and that is the LaTex output :)

NOW  I WILL TALK ABOUT THE ACTUAL QUESTION.

$$3^2*\sqrt{5}=9*\sqrt5 = 9\sqrt5$$

The * sign can be invisable.  :)

This is an irrational number so it is already the best exact answer.

The answer you gave is an approximation :)

the answer will be 3.343701

$$3^2*sqrt(5)$$

$${{\mathtt{3}}}^{{\mathtt{2}}}{\mathtt{\,\times\,}}{\sqrt{{\mathtt{5}}}} = {\mathtt{20.124\: \!611\: \!797\: \!498\: \!107\: \!3}}$$

$${{\mathtt{3}}}^{{\mathtt{2}}} = {\mathtt{9}}$$

$${\sqrt{{\mathtt{5}}}} = {\mathtt{2.236\: \!067\: \!977\: \!499\: \!789\: \!7}}$$

rounded

$${\mathtt{9}}{\mathtt{\,\times\,}}{\mathtt{2.236\: \!067\: \!977\: \!5}} = {\mathtt{20.124\: \!611\: \!797\: \!5}}$$