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If α and β are the zeroes of the polynomial x2-4x+3, then form a quadratic polynomial whose zeroes are 3α and 3β.

Question : If α and β are the zeroes of the polynomial x2-4x+3, then form a quadratic polynomial whose zeroes are 3α and 3β.

Doubt by Charu

Solution : 
p(x)=x2-4x+3
a=1
b=-4
c=3

Sum of Zeroes
α+β = -b/a
α+β = -(-4)/1
α+β = 4

Product of Zeroes
αβ = c/a
αβ = 3/1
αβ = 3

For New Polynomial 

Sum of Zeroes (S) 
S= 3
α+3β
S= 3(
α+β)
S= 3(4)
S=12

Product of Zeroes (P)
P= (3
α)(3β)
P= 9(
αβ)
P=9(3)
P=27

New Polynomial will be given by 

p'(x)=x²-Sx+P
p'(x)=x²-(12)x+27
p'(x)=x²-12x+27

which is the required polynomial.