推理:(1)由书中知识,+5的相反数是-5,-5的相反数是5,那么数x的相反数是__-x__.数-x的相反数是__x__.数a-b的相反数是__b-a__.数a+b的相反数是__-a-b___.
数a-b的相反数是
把a-b看做x
则相反数是-(a-b)=-a+b=b-a
数a+b的相反数是
把a+b看做x
则相反数是-(a+b)=-a-
推理:(1)由书中知识,+5的相反数是-5,-5的相反数是5,那么数x的相反数是__-x__.数-x的相反数是__x__.数a-b的相反数是__b-a__.数a+b的相反数是__-a-b___.
数a-b的相反数是
把a-b看做x
则相反数是-(a-b)=-a+b=b-a
数a+b的相反数是
把a+b看做x
则相反数是-(a+b)=-a-