Question

find all the zeros of the polynomial f(x)=(x-3)(x³-9x+20)​

Answer 1

Answer

Correct option is

A

2

1

​  

,1

Twozerosare  

2

​  

and−  

2

​  

so(x−  

2

​  

)

and(x+  

2

​  

)arefactors

orwecansay(x  

2

−2)isafactor

hencetheotherfactoris(2x  

2

−3x+1)

nowtofindrestofzero

2x  

2

−3x+1=0

2x  

2

−2x−x+1=0

2x(x−1)−1(x−1)=0

(x−1)(2x−1)=0

∴x=1orx=(  

2

1

​  

)