We'll impose the constraints of existence of square
roots:
x - 1>=0
x
>= 1
2 -x >=0
x
=<2
The interval of admissible values for x is [1 ;
2].
Now, we'll solve the equation. We'll subtract sqrt(2-x)
both sides:
sqrt(x-1) = 1 -
sqrt(2-x)
We'll raise to square both
sides:
x - 1 = 1 - 2sqrt(2-x)+ 2 -
x
We'll combine like terms:
x
- 1 = 3 -x - 2sqrt(2-x)
We'll subtract 3 - x both
sides:
2x - 4 =
-2sqrt(2-x)
We'll divide by
-2:
2 - x = sqrt(2-x)
We'll
raise to square both sides:
4 - 4x + x^2 = 2 -
x
We'll subtract 2 - x:
x^2 -
3x + 2 = 0
(x-1)(x-2) =
0
x-1=0
x =
1
x-2=0
x
= 2
Since both values belong to the interval
of admissible values, we'll accept them as solutions of the
equation.
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