Question

If α and β are the zeros of the
polynomial f(x)= x² - x- 4 , find
the value of 1/α + 1/β - αβ
-αβ

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Answer 1

Answer:

f(x)=x2−x−4

f(x)=x2−x−4α+β=1

f(x)=x2−x−4α+β=1αβ=−4

f(x)=x2−x−4α+β=1αβ=−4→α1+β1−αβ

f(x)=x2−x−4α+β=1αβ=−4→α1+β1−αβ=αβα+β−αβ

f(x)=x2−x−4α+β=1αβ=−4→α1+β1−αβ=αβα+β−αβ=−41−(−4)

f(x)=x2−x−4α+β=1αβ=−4→α1+β1−αβ=αβα+β−αβ=−41−(−4)=4−1+4

f(x)=x2−x−4α+β=1αβ=−4→α1+β1−αβ=αβα+β−αβ=−41−(−4)=4−1+4=415