ExamBro
ExamBro
JEE Mains · Maths · STD 11 - 7. binomial theoram

माना \(\left(\mathrm{a}+\mathrm{bx}+\mathrm{cx}^2\right)^{10}=\sum_{\mathrm{i}=0}^{20} \mathrm{p}_{\mathrm{i}} \mathrm{x}^{\mathrm{i}}, \mathrm{a}, \mathrm{b}, \mathrm{c} \in \mathbb{N}\) है। यदि \(\mathrm{p}_1=20\) तथा \(\mathrm{p}_2=210\) हैं, तो \(2(\mathrm{a}+\mathrm{b}+\mathrm{c})\) बराबर है :

  1. A \(8\)
  2. B \(12\)
  3. C \(15\)
  4. D \(6\)
Verified Solution

Answer & Solution

Correct Answer

(B) \(12\)

Step-by-step Solution

Detailed explanation

\(\left(a+b x+c x^2\right)^{10}=\sum_{i=0}^{20} p_i x^i\) Coefficient of \(x^1=20\) \(20=\frac{10 !}{9 ! 1 !} \times a^9 \times b^1\) \(a^9 . b =2\) \(a=1, b=2\) Coefficient of \(x ^2=210\) \(210=\frac{10 !}{9 ! 1 !} \times a^9 \times c^1+\frac{10 !}{8 ! 2 !} \times a^8 b^2\)…
Same subject
Explore more questions on app
From JEE Mains
Explore more questions on app