24th of March 2017

If x2-1 is a factor of ax3+bx2+cx+d, show that a+c=0

Vikas Mahajan - CBSE - Class IX

Friday, March 24, 2017 at 18:00:PM


Hi Ananya,

Consider the quadratic equation,x2 +4x+4

The degree of the quadratic equation is 2.

However, if you solve this equation and find the roots, you will realise that you will get only 1 root, that is '2'.

This is cause the roots are repeated. 

That is, why we say atmost which means maximum n roots. 

The same holds for an equation with degree n.

We can always have some equations which have equal (that is, repeated) roots.

Hence, we use the word ATMOST.

Friday, March 24, 2017 at 20:41:PM