Question

Which is the simplified form of r^-7 + s^-12? arrows to the left of -7 and -12 represent exponents,

Answer 1

$a^{-b}=\dfrac{1}{a^b}\\\\ r^{-7}+s^{-12}=\dfrac{1}{r^7}+\dfrac{1}{s^{12}}\implies \text{D}$

Answer 2

Answer is D, 1/r^7 + 1/s^12. Im positive 100%