123²-101²-122*124
=123² - 122 * 123 - 122 - 101²
=123(123-122) - 122 - 101²
=123 - 122 - 101²
=1-101²
=(1+101)(1-101)
=-102*100
=-10200
123²-101²-122*124
=123² - 122 * 123 - 122 - 101²
=123(123-122) - 122 - 101²
=123 - 122 - 101²
=1-101²
=(1+101)(1-101)
=-102*100
=-10200