=(x+2)/(x²-4)+(x-2)/(x²-4)+(x平方+4)分之2x+(x四次方+16)分之4x三次方
=2x/(x²-4)+(x平方+4)分之2x+(x四次方+16)分之4x三次方
=[2x(x²+4)+2x(x²-4)]/(x的4次方-16)+(x四次方+16)分之4x三次方
=4x³/(x的4次方-16)+4x³/(x的4次方+16)
=8x的7次方/(x的8次方-256)

关键点是二项二项通分,合并