find a quadratic polynomial each with the given number as the sum and the product of it's zeros respectively (i) 4 and -2 (ii) 0 and -10/3 (iii) 5/7 and 0 (iv) -5 and -6 (v) √2 and -12 (vi) 3 and -2 (vii) -2√3 and -9 (viii) -3/2√5 and 1/2
Answers
Given
we have given sum and Product of a quadratic polynomial:(i) 4 and -2 (ii) 0 and -10/3 (iii) 5/7 and 0 (iv) -5 and -6 (v) √2 and -12 (vi) 3 and -2 (vii) -2√3 and -9 (viii) -3/2√5 and 1/2
To Find
we have to find the quadratic polynomial
Since, we have given sum and Product of roots of the quadratic polynomial so, we can use this formula to find out the Equation.
x²-(sum of roots)x+ (product of roots)=0
(I) 4 and -2
x²-(4)x+(-2)=0
=> x²-4x-2=0
(ii) 0 and -10/3
x²-(0)x+(-10/3)=0
=> x²-10/3=0
(iii) 5/7 and 0
x²-(5/7)x+(0) =0
=> x²-5/7x=0
(iv) -5 and -6
x²-(-5)x+(-6)=0
=> x²+5x-6=0
(v) √2 and -12
x²-(√2)x+(-12)=0
=>x²-√2x-12=0
(vi) 3 and -2
x²-(3)x+(-2)=0
=>x²-3x-2=0
(vii) -2√3 and -9
x²-(-2√3)x+(-9)=0
=>x²+2√3x-9=0
(viii)-3/2√5 and 1/2
x²-(-3/2√5)x+(1/2)=0
=>x²+3/2√5x+1/2=0
Check:
we can check by factorise the obtained polynomial
(iv) -5 and -6
x²-(-5)x+(-6)=0
=> x²+5x-6=0
Now factorise it
x= -b±√ b²-4ac/2a
a= 1 ,b= 5 & c = -6
x= -5±√5²-4(1)(-6)/2
x= -5±√ 25-(-24)/2
x= -5±√ 25+24/2
x= -5±√49/2
x= -5±7/2
x= -5+7/2 or x = -5-7/2
x= 2/2 or x= -12/2
x= 1 or x = -6
sum of zeroes = -6+1= - 5
product of zeroes= -6*1= -6