no 9 please yg jago mtk

[tex]P(t)=\frac{200t}{t^2+100}[/tex]
Nilai [tex]P(t)[/tex] yang diinginkan adalah:
[tex]P(t) > 8[/tex] (ingat bahwa [tex]P(t)[/tex] dalam ribuan)
sehingga:
[tex]P(t)\ \textgreater \ 8\\\frac{200t}{t^2+100}\ \textgreater \ 8\\200t\ \textgreater \ 8(t^2+100)\\0\ \textgreater \ 8t^2-200t+800\\8t^2-200t+800\ \textless \ 0\\t^2-25t+100\ \textless \ 0\\(t-20)(t-5)\ \textless \ 0\\5\ \textless \ t\ \textless \ 20 \ (E)[/tex]