ExamBro
ExamBro
JEE Mains · Maths · STD 12 - 10. vector algebra

माना \(\overrightarrow{\mathrm{a}}=3 \hat{i}-\hat{j}+2 \hat{k}, \overrightarrow{\mathrm{~b}}=\overrightarrow{\mathrm{a}} \times(\hat{i}-2 \hat{k})\) और \(\overrightarrow{\mathrm{c}}=\overrightarrow{\mathrm{b}} \times \hat{k}\)। तब \(\overrightarrow{\mathrm{c}}-2 \hat{j}\) का \(\vec{a}\) पर प्रक्षेप क्या है?

  1. A \(2 \sqrt{14}\)
  2. B \(\sqrt{14}\)
  3. C \(3 \sqrt{7}\)
  4. D \(2 \sqrt{7}\)
Verified Solution

Answer & Solution

Correct Answer

(A) \(2 \sqrt{14}\)

Step-by-step Solution

Detailed explanation

\begin{aligned} & \overrightarrow{\mathrm{b}}=\overrightarrow{\mathrm{a}} \times(\hat{\mathrm{i}}-3 \hat{\mathrm{k}}) \\ & =\left|\begin{array}{ccc} \hat{\mathrm{i}} & \hat{\mathrm{j}} & \hat{\mathrm{k}} \\ 3 & -1 & 2 \\ 1 & 0 & -2 \end{array}\right|=2 \hat{\mathrm{i}}+8…

Same subject
Explore more questions on app
From JEE Mains
Explore more questions on app