已知x+y=6,x-y=5,则x^2-y^2等于多少

问题描述:

已知x+y=6,x-y=5,则x^2-y^2等于多少

x^2-y^2
=(x+y)(x-y)
=6×5
=30

x^2-y^2=(x+y)(x-y)=6*5=30

x^2-y^2
=(x-y)(x+y)
=5×6
=30