Asked by lisa dunn

These are 2 questions that I need help with from my math assignment. My teacher isn't much help, she doesn't respond ):
1. (2x-31)/(x^2-49) . Identify any nonpermissible values.

2.Using an example, explain why non-permissible values must be noted before simplifying rational expressions and equations


Answers

Answered by oobleck
division by zero is undefined, so you must exclude values where the denominator is zero.
x^2 - 49 = (x-7)(x+7)
so, ...

You have to exclude them before simplifying, because in the original expression, 0/0 is still undefined. Canceling the offending factors makes the fraction simpler, but the original fraction is still undefined where the denominator is zero, even if the numerator is too.
There are no AI answers yet. The ability to request AI answers is coming soon!

Related Questions