Archive
24th of March 2017
Mathematics
Q:

Factorise: 9x2 + 4y2 + z2 -12xy +4yz - 5zx.Hence find its value when x=1,y=2 and z=-1

Nisha_vini29 - CBSE - Class IX

Friday, March 24, 2017 at 17:19:PM

A:

Hi Nisha,

Here is your solution. And the coefficient of zx is -6 not -5. This makes it impossible to use the identity. This was why we took time to solve this. Hope this clears your doubt Nisha.

Monday, March 27, 2017 at 18:47:PM