If the shortest distance between the lines -> r = ( - hat i + 3hat k ) + lambda ( hat i - ahat j ) and -> r = ( - hat j + 2hat k ) + mu ( hat i - hat j + hat k ) is sqrt 2 / 3 , then the integral value of a is equal to ___________.

vec b_1 x vec b_2=|\ccchat i hat j hat k \ 1 -a 0 \ 1 -1 1\|=-a hat i-hat j+(a-1) hat k vec a_1-vec a_2=-hat i+hat j+hat k Shortest distance =|frac(vec a_1-vec a_2) * (vec b_1 x vec b_2)|vec b_1 x vec b_2|| => sqrt((2 / 3))=frac2(a-1)sqrta^2+1+(a-1)^2 \ => 6(a^2-2 a+1)=2 a^2-2 a+2 \ => (a-2)(2 a-1)=0 => a=2 because a in z .

If the shortest distance between the lines r i 3 k lam... | null (Mathematics)

\vec{b}_{1} \times \vec{b}_{2}=\left|\begin{array}{ccc}\hat{i} & \hat{j} & \hat{k} \\ 1 & -a & 0 \\ 1 & -1 & 1\end{array}\right|=-a \hat{i}-\hat{j}+(a-1) \hat{k}

\vec{a}_{1}-\vec{a}_{2}=-\hat{i}+\hat{j}+\hat{k}

Shortest distance

=\left|\frac{\left(\vec{a}_{1}-\vec{a}_{2}\right) \cdot\left(\vec{b}_{1} \times \vec{b}_{2}\right)}{\left|\vec{b}_{1} \times \vec{b}_{2}\right|}\right|

\begin{aligned} &\Rightarrow \quad \sqrt{\frac{2}{3}}=\frac{2(a-1)}{\sqrt{a^{2}+1+(a-1)^{2}}} \\\\ &\Rightarrow 6\left(a^{2}-2 a+1\right)=2 a^{2}-2 a+2 \\\\ &\Rightarrow \quad(a-2)(2 a-1)=0 \Rightarrow a=2 \text { because } a \in z . \end{aligned}

Explanation

The minimum number of elements that must be added to the relation R = {(a,b),(b,c),(b,d)} on the set { a,b,c,d} so that it is an equivalence relation is

For integers n and r let n r nCr ifn ge r ge 0 0 otherwise

The integral int_0^1 \frac{1}{7^{\left[\frac{1}{x}\right]}} {dx}, where [.] denotes the greatest integer function is equal to

The area of the region enclosed by the parabolas y=4x-x^2 and 3y=(x-4)^2 is equal to

For (2 leq r leq n,binom{n}{r} + 2binom{n}{r - 1} + binom{n}{r - 2} =)

Ten different letters of an alphabet are given. Words with five letters are formed from these given letters. Then the number of words which have atleast one letter repeated, is

Area of the region (x,y):x^2+(y-2)^2≤4,x^2≥2y is

Let R be the set of real numbers. end{enumerate} Statement-1: A = {(x,y) in R X R:y - x is an integer } is an equivalence . relation on R. Statement-2: B = {(x,y) in R X R:x = alpha y for some rational number } is . an equivalence relation on R.

In a college of 300 students, every student reads 5 newspapers and every newspaper is read by 60 students. The number of newspaper is

Download Divine JEE App

Quick Links

Exam Categories

Contact Info

Divine JEE