Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert
If $\alpha, \beta, \gamma$ are the roots of the equation $x^{3}-3 x^{2}+2 x-1=0$, then the value of $(1-\alpha)(1-\beta)(1-\gamma)$ is
MathematicsQuadratic EquationCOMEDKCOMEDK 2012
Options:
  • A 1
  • B 2
  • C $-1$
  • D $-2$
Solution:
1382 Upvotes Verified Answer
The correct answer is: $-1$
We have,
$x^{3}-3 x^{2}+2 x-1$
So, $\quad \alpha+\beta+\gamma=3$
$\alpha \beta+\beta \gamma+\gamma \alpha=2$
$\alpha \beta \gamma=1$
Now, $(1-\alpha)(1-\beta)(1-\gamma)$
$=1-(\alpha+\beta+\gamma)+(\alpha \beta+\beta \gamma+\gamma \alpha)-\alpha \beta \gamma$
$=1-3+2-1=-1$

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.