Hi,
For some reason, when I calcurate the answer is -4.... but the answer should be A) - can anyone please help?
ps 500 test21 #11
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The above expression can be simplified as:
Taking LCM:
Denominator would be (z-3)(z-1)
so (z-3)(z+3) + (z+1)(z-1) / (z-3)(z-1) = 2
z^2-9 + z^2 - 1 = 2 (z-3)(z-1)
2z^2 - 10 = 2(z^2 - 4z + 3)
2z^2 - 10 = 2z^2 - 8z + 6
Cancel 2z^2 on both sides
so, 8z = 16
and z= 2.
Taking LCM:
Denominator would be (z-3)(z-1)
so (z-3)(z+3) + (z+1)(z-1) / (z-3)(z-1) = 2
z^2-9 + z^2 - 1 = 2 (z-3)(z-1)
2z^2 - 10 = 2(z^2 - 4z + 3)
2z^2 - 10 = 2z^2 - 8z + 6
Cancel 2z^2 on both sides
so, 8z = 16
and z= 2.
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(z+3/z-1) + (z+1/z-3) = 2
{[(z+3)*(z-3)] + [(z+1)*(z-1)]} / (z-1)(z-3) = 2
z^2 - 9 + z^2 - 1 = 2 {z^2 - 3z - z + 3}
(z^2 - 5) = z^2 - 4z + 3
-4z = -8
Thus z = 2
{[(z+3)*(z-3)] + [(z+1)*(z-1)]} / (z-1)(z-3) = 2
z^2 - 9 + z^2 - 1 = 2 {z^2 - 3z - z + 3}
(z^2 - 5) = z^2 - 4z + 3
-4z = -8
Thus z = 2