Question

Zeros of a polynomial 3x square-kx+6 is 3 find k

Answer 1

$\blue{\bold{\underline{\underline{Answer:}}}}$

$\green{\tt{\therefore{Value\:of\:k=11}}}$

$\orange{\bold{\underline{\underline{Step-by-step\:explanation:}}}}$

$\green{\underline \bold{given: }} \\ \tt: \implies {3x}^{2} - kx + 6 = 0 \\ \\ \tt: \implies zeroes \: of \: polynomial = 3 \\ \\ \red{\underline \bold{to \: find: }} \\ \tt: \implies value \: of \: k = ?$

• According to given question :

$\bold{as \: we \: know \: that} \\ \tt: \implies {3x}^{2} - kx + 6 = 0 \\ \\ \tt \circ \: x = 3 \\ \\ \tt: \implies 3 \times {3}^{2} - k \times 3 + 6 = 0 \\ \\ \tt: \implies 3 \times 9 - 3k + 6 \\ \\ \tt: \implies 27 + 6 - 3k = 0 \\ \\ \tt: \implies 33 = 3k \\ \\ \tt: \implies \frac{33}{3} = k \\ \\ \green{\tt: \implies k = 11} \\ \\ \blue{\bold{some \: related \: formula }} \\ \orange{\tt \circ \: d = {b}^{2} - 4ac} \\ \\ \orange{\tt \circ \: x = \frac{ - b \pm \sqrt{d} }{2a} }$

Answer 2

$</p><p>\tt{\huge{\pink{Hello!!! }}}$

$\tt{ \purple{ \implies{f(x) = 3 {x}^{2} - kx \: + 6}}}.......(1)$

Zeroes : 3

Placing in the above equation ,

$\tt{\ red { \implies{ f(3) = 3 {3}^{2} - k.3 \: + 6}}}.......(2)$

$\tt {\red { => K = 11 }}$