Question

已知ab互为相反数cd互为倒数,x的绝对值等于3

Answer 1

a,b互为相反数,则 a+b=0

c,d互为倒数,则cd=1

|x|=3,则 x=3 或 x=-3

当x=3时：

|x|-(a+b+cd分之1)x-cd

=3-1×3-1

=3-3-1

=-1

当x=-3时：

|x|-(a+b+cd分之1)x-cd

=3-1×(-3)-1

=3+3-1

=5

解补充题：

原式=7.41×(-5/13)-3×5/13+0.51×5/13

=-7.41×5/13-3×5/13+0.51×5/13

=(-7.41-3+0.51)×5/13

=-(7.41+3-0.51)×5/13

=-9.9×5/13

=-99/10×5/13

=-99/26