It's my friend's dad's birthday and we wrote him an equation to which the answer is his age (he doesn't know that). It's nothing spectacular, we only had like 15 min and this probably child's play to most of you, but try to find his age. btw we are only in precalc so no complex concepts.

LaTex doesn't really make this evident (probably due to my lack of knowledge of LaTex) but i is to the power of (log 10^17)(-2)(cos 14pi/2).