Complex Numbers And Quadratic Equations question 517
Question: If $ \alpha $ and $ \beta $ are the roots of the equation $ 4x^{2}+3x+7=0 $ , then $ \frac{1}{\alpha }+\frac{1}{\beta } $ = [MNR 1981; RPET 1990]
Options:
A) $ -\frac{3}{7} $
B) $ \frac{3}{7} $
C) $ -\frac{3}{5} $
D) $ \frac{3}{5} $
Show Answer
Answer:
Correct Answer: A
Solution:
Given equation $ 4x^{2}+3x+7=0 $ , therefore $ \alpha +\beta =-\frac{3}{4} $ and $ \alpha \beta =\frac{7}{4} $ Now $ \frac{1}{\alpha }+\frac{1}{\beta }=\frac{\alpha +\beta }{\alpha \beta }=\frac{-3/4}{7/4}=\frac{-3}{4}\times \frac{4}{7}=-\frac{3}{7} $ .
BETA
