Question

Find the value of a for which (x-2) is a factor 3x2+ax2+x-2 show that for this value of a, the cubic equation 3x3+ax2+x-2=0 has only real root
(OCR 2014)
Tolong dong yg paling pintar matematika bisa gk

Answer 1

3x³ + ax² + x - 2
= x² (3x + a) + 1(x-2)

Agar dapat mempunyai akar real maka 3x + a haruslah habi dibagi x-2
Maka nilai a = -6 karena 3(x-2) = 3x -6

Jadi jawabannya adlah a = -6
Semoga bermanfaat... :)