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PHP

Lee-Ann Huber
Lee-Ann Huber
534 Points

PHP Pow() with negative exponent

Hoping someone can help me. I'm creating a mortgage calculator that works out the bond you can afford based on your salary, loan term and interest rate.

I'm struggling with the results because the exponent in the formula is negative. I know I need to use the POW() function, but I'm clearly doing it wrong as the answer comes back wrong. I'm completely new to PHP so converting this formula to PHP is becoming quite daunting for me, could anyone help? $affordability = (1-(1+$monthlyinterest)^(-$loanterm*12))/$monthlyinterest

I have it as: $affordability = (1-pow((1+$monthlyinterest),(-$loanterm*12)))/$monthlyinterest