Is $$(1/a^2 + 1/a^4 + 1/a^6 +...) > (1/a + 1/a^3 + 1/a^5 +...)$$?
A. $$0< a \leq 1$$
B. One of the roots of the equation $$4x^2-4x+1 = 0$$ is a
Consider the first statement:
When the common ratio is less than 1 we can apply the formula of sum of infinite terms.
So, LHS = $$1/(a^2 - 1)$$
RHS = $$a/(a^2 - 1)$$
If a<1 then LHS<RHS
If a = 1,then LHS = RHS
So, we cannot answer the question using statement 1 alone
Using statement 2 alone, we know that a = 1/2. So, RHS > LHS
Hence, option a)
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