Question

11. Ifa, are zeroes of the polynomial 2x2 – 5x - 4, then
1/a+1/b​

Answer 1

${\large{\sf{2x²-5x-4}}}$

${\large{\boxed{\sf{a+b=\frac{-(-5)}{2}=\frac{5}{2}}}}}$

${\large{\boxed{\sf{ab=\frac{-4}{2}=-2}}}}$

$\large{→}$ ${\large{\boxed{\sf{\frac{1}{a}+\frac{1}{b}}}}}$

= ${\large{\boxed{\sf{\frac{a+b}{ab}}}}}$

= ${\large{\boxed{\sf{\frac{\frac{5}{2}-2}{\frac{5}{2}×(-2)}}}}}$

= ${\large{\boxed{\sf{\frac{\frac{1}{2}}{-5}}}}}$

= ${\large{\boxed{\red{\sf{-\frac{1}{10}}}}}}$

Answer 2

Answer:

Polynomial=2x²-5x-4

a+b=5/2

ab= (-2)

1/a+1/b=a+b/ab

=5/2÷(-2)

=5/2×(-1/2)

= (-5/4)