Himpunan penyelesaian dari Log pangkat2 x+logx=log100 adalah a.{-2,10} b.{2,10} c.{1,10} d.{1/100,10} e.{10,100}

Logaritma
SMA Kelas X

log²x + logx = log100
log²x + logx = log10²
log²x + logx = 2. log10
log²x + logx = 2

misal logx = a
a² + a = 2
a² + a - 2 = 0
(a + 2)(a - 1) = 0

a + 2 = 0
a = -2

dan

a - 1 = 0
a = 1

a = -2
logx = -2
x = 10⁻²
   = 1/100

a = 1
logx = 1
x = 10¹
   = 10

HP = {1/100, 10}    ====> [D]