Minta bantuan nya no 8 dan 9. :)

Minta bantuan nya no 8 dan 9. 🙂

Jawaban Terkonfirmasi

Nomor 8
Artinya s ≥ 8
Maka:
$displaystyle frac{200t}{t^2+100}ge8 \\ frac{200t}{t^2+100}-8ge0 \\ frac{200t-8(t^2+100)}{t^2+100}geq0 \\ frac{200t-8t^2-800}{t^2+100}ge 0 \\ frac{-8t^2+200t-800}{oplus}ge 0 \\ -8t^2+200t-800ge0 \ t^2-25t+100leq 0 \ (t-5)(t-20)leq 0 \ 5$
Pilihan : D

Nomor 9.
Dua akar real berbeda, D > 0
$b^2-4ac>0 \ (a-1)^2-4.1(-a+4)>0 \ a^2-2a+1+4a-16>0 \ a^2+2a-15>0 \ (a+5)(a-3)>0 \ a3$
Pilihan : A