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MathsMediumMCQ2023 · 24 Jan Shift 1

Q63.The value of ∑𝑟=22 0 22𝐶𝑟· 23𝐶𝑟 is (1) 45𝐶23 (2) 44𝐶23 (3) 45𝐶24 (4) 44𝐶22

What This Question Tests

The problem requires using De Moivre's theorem to simplify a complex number raised to a power, then equating real and imaginary parts to find p and q, and finally forming a quadratic equation from the given roots.

Concepts Tested

Polar form of complex numbersDe Moivre's theoremRoots of quadratic equationSum and product of roots

Formulas Used

(cosθ + i sinθ)ⁿ = cos(nθ) + i sin(nθ)

x² - (sum of roots)x + (product of roots) = 0

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