Sequences & Series
Harmonic Progression
Grade 11
Question:
<p>For triangle ABC, if <span style="text-decoration: overline;">cosecA</span>, cosecB, cosecC are in H.P., then the possible value(s) of <span style="text-decoration: overline;">a}</span> will be</p><p>(where a, b, c denote lengths of sides of △ABC as in usual notation)</p>
Step-by-Step Solution
Key Concept: When cosecA, cosecB, cosecC are in H.P., their reciprocals (sinA, sinB, sinC) are in A.P. Use the sine rule and properties of triangles to find constraints on the sides.
<p>This is a Match the Column problem. The question requires matching with Column-II. Answer corresponds to (R) 5</p>
Correct Answer: R