Damage / Defense damage system

Hello there.

i have a question. i programming a rpg right now. there are different values like strength, dexterity, intelligence
weapons with different damage.

for damage output i got one variable → damageAttack

for the enemy i have one varibble for defense → enemyDefense

now i buildet a formule to manage this. the goal was if a new player with less attack damage fight against a good player with huge defense still do damage. my first formula was

damageOutput = damageAttack - (enemyDefense / 10)

the problem is like writen before. if a new player fight against a good one.

For example de attacker got attack value of 2, the defender a armor value of 50

calculated → damageOutput = 2 - (50 / 10) = -3

so de attacker mack -3 damage. thats not the goal i want.

so i created i limes graph (attached file)

like that:

damageOutput = damageAttack ^ (-(enemyDefense / 100) * 0.3) * damageAttack ;

this formula works great in excel

lets try with some values

Attack = 2
Defense = 50

damageOutput = 2 ^ (-(50/ 100) * 0.3) * 2 = 1.8

i tryied to add this formula to unity but it doesn work.

can someone help me? unity dont accept this symbol ^ so what i have to do?

mathf.pow or mathf.exp?

im really thankful if someone can help me.

Mathf.Pow(damageAttack, (-(enemyDefense * 0.01f) * 0.3f)) * 2