(4c+3y)/(c^2-y^2)-3/(c-y)

(4с+3y)/[(с-y)(с+y])-3/(с-y)=(4c+3y-3c-3y)/(c²-y²)=c/(c²-y²)

[latex] \frac{4c+3y}{ c^{2} - y^{2} } - \frac{3}{c-y} = \frac{4c+3y}{ c^{2} - y^{2} } - \frac{3(c+y)}{(c-y)(c+y)} = \frac{4c+3y}{ c^{2} - y^{2} } - \frac{3c+3y}{ c^{2} - y^{2} } = \frac{4c+3y-3c-3y}{ c^{2} - y^{2} } = \\ = \frac{c}{ c^{2} - y^{2} } \\ [/latex]