I see what you're trying to do!

Correcting the Equation:
3^3 indeed equals 3_3_3, which is:

3^3 = 3_3_3 = 27

However, the second part of your equation:

3+3+3+3+3+3+3+3+3

is actually:

3 (added 9 times) = 27

So, while your second equation isn't the conventional way to calculate 3^3, it does arrive at the correct answer!

Keep in mind that exponentiation (3^3) is a shorthand way to represent repeated multiplication, whereas your second equation represents repeated addition.