If we know that a and B are opposite to each other and C and D are reciprocal to each other, then A-CD + B=______ .

If we know that a and B are opposite to each other and C and D are reciprocal to each other, then A-CD + B=______ .

From the meaning of the title, we can get a + B = 0, CD = 1, A-CD + B = a + B-Cd = 0-1 = - 1