jee_main_2025_28_jan_morning - Permutations and Combinations Topics

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Sample Questions in this Chapter

QUESTION #0 Permutations under Restrictions
The number of different 5 digit numbers greater than 50000 that can be formed using the digits 0, 1, 2, 3, 4, 5, 6, 7, such that the sum of their first and last digits should not be more than 8, is
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QUESTION #0 Combinatorial Coefficients and Locus
Let ⁿCr - 1 = 28, ⁿCᵣ = 56 and ⁿCr + 1 = 70. Let A(4cost, 4sint), B(2sint, -2cost) and C(3r - n, r² - n - 1) be the vertices of a triangle ABC, where t is a parameter. If (3x - 1)² + (3y)² = α, is the locus of the centroid of triangle ABC, then α equals:
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Rankbit System
JEE Physics: Waves (+15.5%) | Electrostatics: Concentric Shells (-29.7%) | Modern Physics: Photoelectric Clones (+34.2%) | Mathematics: Definite Integrals (+18.1%) | Chemistry: Coordination Splitting (-11.4%) | JEE Physics: Waves (+15.5%) | Electrostatics: Concentric Shells (-29.7%) | Modern Physics: Photoelectric Clones (+34.2%) | Mathematics: Definite Integrals (+18.1%) | Chemistry: Coordination Splitting (-11.4%)

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