Polynomials Help! (AGAIN) (1 Viewer)

[fatima96]

Form a cubic eqn with the following roots

View attachment 27642

 

[Sup3rDry]

(x-2)(x-3)(x-5)

Expand and simplify.

 

[fatima96]

(x-2)(x-3)(x-5)

Expand and simplify.

OH MY GOD I AM THE BIGGEST IDIOT TO EXIST ON PLANET EARTH
thank you

 

[Sy123]

I reckon this would be faster:

 

[HeroicPandas]

(x-2)(x-3)(x-5)

Expand and simplify.

Alternatively, you can use sum of roots, sum of roots 2 at a time and product of roots, and letting the polynomial be P(x) = x^3 + bx^2 + cx + d

Eg. 2 +3 + 5 = -b............. etc

 

[fatima96]

how about if the roots were ,

\[1, (1+\sqrt{2}), (1-\sqrt{2})\]

 

[fatima96]

how about if the roots were ,

 

[Sup3rDry]

Yep definitely there are alternative ways. Not saying that my way of working was the only one.

 

[fatima96]

how about if the roots were ,

View attachment 27642

 

[Sup3rDry]

how about if the roots were ,

View attachment 27642

You can use that formula Sy123 posted.

 

[fatima96]

You can use that formula Sy123 posted.

Thanks alot, you guys really helped