a) (x-32).45=90 b) 3^2x+1=81 c)(x-1/3)^2-1/4=0

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1. a) (x-32).45=90

   x-32=90:45

   x-32=2

   x=2+32

   x=34

   b)3^2x+1=81

   3^2x=81-1

   9x=80

   x=80:9

   => x ∈∅

   c)(x-1/3)^2-1/4=0

   (x-1/3)^2=0+1/4

   (x-1/3)^2=1/4

   (x-1/3)^2=(±1/2)^2

   => x-1/3=±1/2

   TH1:

   x-1/3=1/2

   x=1/2+1/3

   x=3/6+2/6

   x=5/6

   TH2:

   x-1/3=-1/2

   x=-1/2+1/3

   x=-3/6+2/6

   x=-1/6

   #chucbanhoctot

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2. a) `(x-32).45 = 90`

   `x-32=90:45`

   `x-32=2`

   `x=2+32`

   `x=34`

   b) `3^(2x + 1)=81`

    `3^(2x+1) = 3^4`

   `2x+1=4`

   `2x=3`

   `x=3/2`

   c) `(x-1/3)^2 -1/4 =0`

   `(x-1/3)^2 = 1/4`

   `(x-1/3) = \pm 1/2`

   `x = 5/6` hoặc `x=-1/6`

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