গণিত • MIST • মিলিটারি ইনস্টিটিউট অব সায়েন্স অ্যান্ড টেকনোলজি ভর্তি পরীক্ষা ২০২৪-২০২৫

গণিত প্রশ্ন

1.

If α\alpha and β\beta are distinct and α2=5α−3\alpha^2 = 5\alpha - 3 and β2=5β−3\beta^2 = 5\beta - 3, then determine the quadratic equation whose roots are αβ\frac{\alpha}{\beta} and βα\frac{\beta}{\alpha}.

উত্তর ও ব্যাখ্যা

AI-তৈরি নমুনা উত্তর

Given that α\alpha and β\beta are distinct and satisfy:
α2=5α−3  ⟹  α2−5α+3=0\alpha^2 = 5\alpha - 3 \implies \alpha^2 - 5\alpha + 3 = 0
β2=5β−3  ⟹  β2−5β+3=0\beta^2 = 5\beta - 3 \implies \beta^2 - 5\beta + 3 = 0

Thus, α\alpha and β\beta are the roots of the quadratic equation:
x2−5x+3=0x^2 - 5x + 3 = 0

By Vieta's formulas:
α+β=5\alpha + \beta = 5
αβ=3\alpha\beta = 3

We need to find the quadratic equation whose roots are αβ\frac{\alpha}{\beta} and βα\frac{\beta}{\alpha}.

Sum of the roots:
S=αβ+βα=α2+β2αβ=(α+β)2−2αβαβ=52−2(3)3=25−63=193S = \frac{\alpha}{\beta} + \frac{\beta}{\alpha} = \frac{\alpha^2 + \beta^2}{\alpha\beta} = \frac{(\alpha + \beta)^2 - 2\alpha\beta}{\alpha\beta} = \frac{5^2 - 2(3)}{3} = \frac{25 - 6}{3} = \frac{19}{3}

Product of the roots:
P=αβ⋅βα=1P = \frac{\alpha}{\beta} \cdot \frac{\beta}{\alpha} = 1

Therefore, the required quadratic equation is:
x2−Sx+P=0x^2 - Sx + P = 0
x2−193x+1=0x^2 - \frac{19}{3}x + 1 = 0
  ⟹  3x2−19x+3=0\implies 3x^2 - 19x + 3 = 0

আরও প্রশ্ন অনুশীলন করতে অ্যাপে যাও

সম্পর্কিত প্রশ্ন