It is known that a and B are opposite to each other, C and D are reciprocal to each other, and the absolute value of X is 5. Try to find the value of 2x - (a + B + CD) x1998 + (- CD) 1999 There is no multiplication sign in the formula, it's X!

It is known that a and B are opposite to each other, C and D are reciprocal to each other, and the absolute value of X is 5. Try to find the value of 2x - (a + B + CD) x1998 + (- CD) 1999 There is no multiplication sign in the formula, it's X!

a+b=0
cd=1
therefore
2x-(a+b+cd)x1998+(-cd)1999
=2x-1998x-1999
=-1996x-1999
When x = 5, = - 11979
When x = - 5, = 7981