Question

if x = -1, y = 2, z = -1, then prove that x -(y-z) is not equal to (x-y)-z

Answer 1

Hi ,

It is given that ,

x = -1 , y = 2 , z = -1

x - ( y - z )

= ( - 1 ) - [ 2 - ( - 1 ) ]

= -1 - ( 2 + 1 )

= -1 - 3

= -4 ----( 1 )

( x - y ) - z

= [ -1 - 2 ] - ( - 1 )

= -3 + 1

= - 2 -------( 2 )

From ( 1 ) and ( 2 ) , we conclude that

x - ( y - z ) ≠ ( x - y ) - z

I hope this helps you.

: )

Answer 2

Putting the values in x-(y-z)

-1 - { 2 - (- 1) }

-1 - (2+1)

-1 - 3

-4

Solution of x -( y -z) is -4

-------------------------------


( x - y) - z

Putting the values,

(-1 -2)-(-1)

(-3) + 1

-3+1

-2

------------------------

It can be noticed that -4 is not equal to -2

So,

x - (y -z) is not equal to ( x -y)-z




I hope this will help you


-by ABHAY