Question 1051099
find the value or values of a in the 
domain of f for which f(a) equals the given number. 
f(x)=x^2+2x-2; f(a)= -1 
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a^2 + 2a -2 = -1
a^2 + 2a -1 = 0
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a = [-2 +- sqrt(4-4*1*-1)]/2
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a = [-2 +- sqrt(8)]/2
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a = [-2 +- 2sqrt(2)]/2
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a = -1 + sqrt(2) or a = -1 - sqrt(2)
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Cheers,
Stan H.
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