Equation to equal 25

1. Jul 2, 2013

starphlo

Not sure where to put this...Could anyone give me a long equation to equal 25? I would like to put it on my son's birthday cake. He will be studying physics this fall in college. Thank you very much!

2. Jul 2, 2013

MarneMath

Since no one else has replied, just do this:

$\int_{0}^{5}2xdx$

3. Jul 2, 2013

DiracPool

How about the square root of 5^4.

$$\sqrt{5^4}$$

That should fit on a birthday cake quite succinctly

Edit: Marne's is pretty good too.

4. Jul 20, 2013

collinsmark

Since he's going to be 25 years old, keeping the numbers '2' and '5' as the predominate numerals could be good.

For something really succinct, you might just try

$$5^2$$

Or if you want to get even crazier, you might try something like (slightly borrowing from MarneMath)

$$\sum_{n = 0}^\infty \frac{1}{2^n} - 2e^{5i \pi} +\int_2^5 2xdx$$

Last edited: Jul 20, 2013
5. Jul 20, 2013

collinsmark

Or, throwing in a few more 2s and 5s,

$$\frac{5}{2}\sum_{n = 0}^\infty \frac{1}{2^n} - e^{(2)(5)i \pi} +\int_2^5 2xdx$$

Or, if you prefer,

$$\frac{5}{2}\sum_{n = 0}^\infty \frac{1}{2^n} + e^{25 i \pi} +\int_2^5 2xdx$$

Be mindful of matching the "+" vs "-" and the "(2)(5)" vs "25" in each of the "e" term of each formula. It makes a difference.