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Algebra Difficulty 3.0 AMC 10/12 Find the answer

Given that the sequence {an}\{a_{n}\} is a geometric sequence, and a2a6+2a42=π{a_2}{a_6}+2{a_4}^2=π, then tan(a3a5)=(  )\tan (a_{3}a_{5})=\left(\ \ \right)

Pick one

Solution

Given that {an}\{a_{n}\} is a geometric sequence, we can use the properties of geometric sequences to find relationships between its terms. Specifically, for a geometric sequence, the product of terms equidistant from the ends is constant. This means that a2a6a_{2}a_{6} and a3a5a_{3}a_{5} should be equal to a42{a}_{4}^{2}, as they are equidistant pairs.

Starting from the given equation:
a2a6+2a42=πa_{2}a_{6} + 2{a_{4}}^{2} = \pi

Given the property of geometric sequences:
a2a6=a3a5=a42a_{2}a_{6} = a_{3}a_{5} = {a}_{4}^{2}

Substituting a3a5=a42a_{3}a_{5} = {a}_{4}^{2} into the equation, we get:
a2a6+2a42=3a3a5=πa_{2}a_{6} + 2{a_{4}}^{2} = 3a_{3}a_{5} = \pi

From this, we can solve for a3a5a_{3}a_{5}:
a3a5=π3a_{3}a_{5} = \frac{\pi}{3}

Knowing that tan(π3)=3\tan\left(\frac{\pi}{3}\right) = \sqrt{3}, we can find the value of tan(a3a5)\tan(a_{3}a_{5}):
tan(a3a5)=tan(π3)=3\tan(a_{3}a_{5}) = \tan\left(\frac{\pi}{3}\right) = \sqrt{3}

Therefore, the correct answer is:
A\boxed{A}

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Source: NuminaMath-1.5, licensed Apache-2.0. Statement and solution reproduced as published; topic and difficulty added by this site.