alleryThe term independent of x in the expansion of (x + 1/x)^6 is
A1
B15
C20
D6
Answer & Solution
Correct answer: C. 20
General term T_(r+1) = ⁶C_r · x^(6−r) · x^(−r) = ⁶C_r · x^(6−2r).
For x⁰, set 6 − 2r = 0 ⇒ r = 3. Coefficient = ⁶C_3 = 20.
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