Answer
$\frac{2b^{2}-3ab+4a^{2}}{a^{2}b^{2}}$
Work Step by Step
$\frac{2}{a^{2}}-\frac{3}{ab}+\frac{4}{b^{2}}$
Find the lowest common denominator (i.e. $a^{2}b^{2}$) and adjust the fractions accordingly:
$=\frac{2\times b^{2}}{a^{2}\times b^{2}}-\frac{3\times ab}{ab\times ab}+\frac{4\times a^{2}}{b^{2}\times a^{2}}$
Expand any brackets and simplify if possible:
$=\frac{2b^{2}}{a^{2}b^{2}}-\frac{3ab}{a^{2}b^{2}}+\frac{4a^{2}}{a^{2}b^{2}}$
Combine the fractions:
$=\frac{2b^{2}-3ab+4a^{2}}{a^{2}b^{2}}$
