Final answer:
To show that (y-1)ⁿ = yⁿ for any whole number n and any positive number y, we can expand both sides using the binomial theorem. By substituting y-1 for a and 1 for b, we can simplify the expression and prove that (y-1)ⁿ = yⁿ.
Step-by-step explanation:
To show that (y-1)ⁿ = yⁿ, we can expand both sides using the binomial theorem. The binomial theorem states that for any positive number y and any whole number n, (a + b)ⁿ = aⁿ + nan⁻¹b + n(n-1)aⁿ⁻²b²/2! + ...
When we substitute y-1 for a and 1 for b in the binomial theorem, we get (y-1 + 1)ⁿ = (y-1)ⁿ + n(y-1)ⁿ⁻¹ + n(n-1)(y-1)ⁿ⁻²/2! + ...
By simplifying, we find that (y-1 + 1)ⁿ = (y-1)ⁿ + n(y-1)ⁿ⁻¹ + n(n-1)(y-1)ⁿ⁻²/2! + ... is equal to yⁿ. Therefore, (y-1)ⁿ = yⁿ is always true, regardless of the values of n and y.