24th of March 2017

In number of zeros for given degrees we writ for quadartic polynomial as at most 2 real zeros . For cubic we write at most 3 real zeros. So my question is why there is not the same number of zeros as degrees , and how can these zeros be less like for quadratic only 1 real zero.

Please help me out.

Ananay Chaudhry - CBSE - Class X

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