已知x=2.8 y=-4又1/5,z=-1又4/5,求代数式-x+y丨-z丨的值
问题描述:
已知x=2.8 y=-4又1/5,z=-1又4/5,求代数式-x+y丨-z丨的值
答
x=2.8 --> x=14/5
y=-21/5
z=-9/5
-x+y|-z| = -14/5 -21/5*|9/5|
=-14/5-21/5*9/5
=-(14/5+189/25)
=-249/25