"*" represents a new operation, its meaning is a * b = - A * B - (a + b). Find: (1) 3 * 5; (2) (- 3) * - 5
"*" represents a new operation, which means a * b = - A * B - (a + b)
(1)3*5=3*5-(3+5)=15-8=7
(2)(-3)*(-5)=[(-3)*(-5)-(-3-5)=15+8=23
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