How do you solve #abs(x^2 - 9 )= x^2 - 9#?

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Answer 1 · 2018-07-10T07:49:49

The solutions are #S={-3,3}#

The equation is

#|x^2-9|=x^2-9#

Therefore,

#{(x^2-9=x^2-9),(x^2-9=-x^2+9):}#

#<=>#, #{(O/),(2x^2-18=0):}#

#<=>#, #{(O/),(x^2-9 =0):}#

#<=>#, #{(O/),((x+3)(x-3) =0):}#

#<=>#, #{(x=-3),(x=3):}#

The solutions are #S={-3,3}#