Roots Of Polynomials

Question 1

How to find the sum and products of these

Answer 1

Yiu know quadratic will have solutions alpha and beta , and a factored out

Expanding this and equating coeffeicnts you realise that AFTER DIFIDING BY A , -b is the sum and c is the product of the roots

You will see this pattern continue

Thus divide first, and -b is the sum, so b is inverse sign and c is just the sign

Question 2

Quartic

Answer 2

6 pairs
4 threes
1 one

Cubic
3paies

Question 3

Substition methif

Answer 3

Substitution method

Make alpha the subject of the formula for z and sub in

Question 4

Get two values, sub bith in and you might get the same so don’t worry

Question 5

Ways to find third root instead of long expansion and then division?

Answer 5

JUST INPUT INTO SUM OF ROOTS THING AS THEY IMGSINSRY WIKK CSNCEL OUT INLY HAVE ONE UNKNOWN!

Question 6

When to use division and when not

Answer 6

Only use it when you have to in the quadratics, for cubics don’t need ro