2.6 Finding the Sum of Roots (SoR) and Product of Roots (PoR)
Example
Find the sums and products of the roots of the following equations.
a. x2+7x−3=0
b. x(x−1)=5(1−x)
Answer:
(a)
x2+7x−3=0a=1, b=7, c=−3Sum of Rootsα+β=−ba=−71=−7Product of Rootsαβ=ca=−31=−3
(b)
x(x−1)=5(1−x)x2−x=5−5xx2−x+5x−5=0x2+4x−5=0a=1, b=4, c=−5Sum of Rootsα+β=−ba=−41=−4Product of Rootsαβ=ca=−51−5
Find the sums and products of the roots of the following equations.
a. x2+7x−3=0
b. x(x−1)=5(1−x)
Answer:
(a)
x2+7x−3=0a=1, b=7, c=−3Sum of Rootsα+β=−ba=−71=−7Product of Rootsαβ=ca=−31=−3
(b)
x(x−1)=5(1−x)x2−x=5−5xx2−x+5x−5=0x2+4x−5=0a=1, b=4, c=−5Sum of Rootsα+β=−ba=−41=−4Product of Rootsαβ=ca=−51−5