Final answer:
The equivalent expression to the given fraction [(y+1)(y-1)/2 ÷ (y+1)/(y-1)] is (y-1)/2 by canceling out common terms in the numerator and the denominator.
Step-by-step explanation:
To find the expression equivalent to the complex fraction [(y+1)(y-1)/2 ÷ (y+1)/(y-1)], we need to follow a step-by-step process. First, understand the operation: division of fractions is the same as multiplication by the reciprocal. So, re-write the expression by keeping the first fraction and multiplying by the reciprocal of the second:
[(y+1)(y-1)/2] × [(y-1)/(y+1)]
Next, simplify by canceling out terms that appear both in the numerator and the denominator. The terms (y+1) in the first fraction's numerator and the second fraction's denominator cancel each other out. Similarly, the (y-1) terms cancel out:
[(y-1)/2]
Therefore, the equivalent expression to the given complex fraction is option A: (y-1)/2.