Find the value of k, if the roots of the equation a 2 x 2 - kx + 9 = 0 are real and unequal.
Answers
Answered by
2
For the roots to be real and unequal, D> 0
Equation is 2x² - kx +9 =0
D = b²- 4ac
=(-k)² - 4×2×9
=k² - 72
∴k² - 72 >0
⇒(k+6√2)(k-6√2) >0
∴k >-6√2 and k>6√2
common part is k > 6√2
Equation is 2x² - kx +9 =0
D = b²- 4ac
=(-k)² - 4×2×9
=k² - 72
∴k² - 72 >0
⇒(k+6√2)(k-6√2) >0
∴k >-6√2 and k>6√2
common part is k > 6√2
Similar questions