fx=3x+2 -1 gx=x-3^-12 +5 fgx=-1013
To find f(g(x)), we substitute g(x) into f(x):
f(g(x)) = 3/(g(x) + 2) - 1
Substituting g(x) = (x-3)^(-1/2) + 5:
f(g(x)) = 3/((x-3)^(-1/2) + 5 + 2) - 1
Simplifying the denominator:
f(g(x)) = 3/((x-3)^(-1/2) + 7) - 1
To find the value of x when f(g(x)) = -10/13, we set the expression equal to -10/13 and solve for x:
-10/13 = 3/((x-3)^(-1/2) + 7) - 1
Multiplying both sides by ((x-3)^(-1/2) + 7):
-10/13 * ((x-3)^(-1/2) + 7) = 3 - ((x-3)^(-1/2) + 7)
Expanding:
-10/13 * (x-3)^(-1/2) - 70/13 = 3 - (x-3)^(-1/2) - 7
Simplifying:
-10/13 * (x-3)^(-1/2) - 70/13 = - (x-3)^(-1/2) - 4
Combining like terms:
-10/13 * (x-3)^(-1/2) + (x-3)^(-1/2) = 70/13 - 4
To simplify the equation further, we can multiply all terms by 13 to eliminate the denominators:
-10 * (x-3)^(-1/2) + (x-3)^(-1/2) = 70 - 52
Simplifying:
-10 * (x-3)^(-1/2) + (x-3)^(-1/2) = 18
Combining like terms:
-9 * (x-3)^(-1/2) = 18
Multiplying both sides by -(1/9):
(x-3)^(-1/2) = -2
To eliminate the exponent, we square both sides:
[(x-3)^(-1/2)]^2 = (-2)^2
Simplifying:
x-3 = 4
Adding 3 to both sides:
x = 7
Therefore, the value of x when f(g(x)) = -10/13 is x = 7
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