Solution
Related Formula
Algebraic factorizations:
x+1 = (x1/3)³ + 1³ = (x1/3+1)(x2/3-x1/3+1) x-1 = (√(x))² - 1² = (√(x)-1)(√(x)+1)Core Logic
Simplify inside the parentheses before using the Binomial general term formula.
Step 1: Simplify Bracket Terms
First fraction:
x+1x2/3-x1/3+1 = x1/3+1Second fraction:
x-1x-x1/2 = (√(x)-1)(√(x)+1)√(x)(√(x)-1) = √(x)+1√(x) = 1 + x-1/2Subtract the two simplified results:
(x1/3+1) - (1+x-1/2) = x1/3 - x-1/2Step 2: Apply Binomial Theorem
The expression simplifies to (x1/3 - x-1/2)¹⁰. Write the general term Tᵣ₊₁:
Tᵣ₊₁ = 10r (x1/3)10-r (-x-1/2)^r = 10r (-1)^r x(10-r)/(3) - (r)/(2)Step 3: Solve for Independent Term
Set the net power of x to zero:
(10-r)/(3) - (r)/(2) = 0 20 - 2r - 3r = 0 5r = 20 r = 4Substitute r=4 into the general term expression:
Coefficient = 104 (-1)⁴ = (10 × 9 × 8 × 7)/(4 × 3 × 2 × 1) = 210Pattern Recognition
The initial fractions look complex but contain simple hidden identities (a³+b³ and a²-b²). Identifying these transforms a daunting fraction expansion into a classic two-term independent coefficient puzzle.
Chapter Mix
Class 11 Mathematics: Binomial Theorem