JEE Main 2021 · MathsNumerical answerNumerical valueMediumCalculation

JEE Main 3 August 2021, Shift 2, Maths Q90

Question 90 of 90 in this shift, Maths question 30 of 30, Section B.

Let

\vec{a} = 2\hat{i} + \alpha\hat{j} + \hat{k}

and

\vec{b} = \beta\hat{i} - 5\hat{j} + \gamma\hat{k}

, where

\alpha

\beta

and

\gamma

are real numbers. If

\vec{a}\times\vec{b} = 26\hat{i} - 11\hat{j} - 19\hat{k}

, then

\alpha - \beta + \gamma

is equal to

\underline{\hspace{2em}}

Official answer

NTA final key.

Chapter: Vector Algebra
Topic: Cross Product
Idea tested: Determinant Calculation Method

Same topic in other shifts

All Cross Product questions

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Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 42 of the 174 JEE Main shifts held from 2017 to 2026.