- #1

coderot

- 10

- 0

My attempt...

[tex](k-1)\left[ x + \left( \frac{4k+3}{k-1} \right)x + \frac{4k-2}{k-1} \right] \le 12.5[/tex]Complete the square on LHS...

[tex](k-1)\left[ \left( x + \frac{4k+3}{2(k-1)} \right)^2 - \frac{48k+1}{4(k-1)^2} \right] \le 12.5[/tex]This boils down to...[tex]-196k \le -98[/tex] and so [tex]k \ge 0.5[/tex]Solution given is: [tex]k \le 0.5[/tex] not sure why. Any help thanks.