Maths

What are the coordinates of the vertices of a cube whose edge is 2 units, one of whose vertices coincides with the origin and the three edges passing through the origin, coincides with the positive direction of the axes through the origin?

Solution: It is given that a cube with 2 units edge, one of whose vertices coincides with the origin and the 3 edges passing through the origin, coincides with the positive direction of the axes...

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Choose the correct answer from the given four options indicated against each of the Exercises if the distance between the points $(\mathrm{a}, 0,1)$ and $(0,1,2)$ is $\sqrt{27}$, then the value of $a$ is
(A) 5
(B) $\pm 5$
(C) 5
(D) none of these

Solution: Option(B) $\pm 5$ Explanation: Suppose $P$ be the point whose coordinate is $(a, 0,1)$ and $Q$ represents the point $(0,$, $(1,2) .$ It is given that, $\mathrm{PQ}=\sqrt{27}$ From the...

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Choose the correct answer from the given four options indicated against each of the Exercises what is the length of foot of perpendicular drawn from the point $P(3,4,5)$ on $y$-axis
(A) $\sqrt{41}$
(B) $\sqrt{34}$
(C) 5
(D) none of these

Solution: Option(B) $\sqrt{34}$ Explanation: As it is known that $y$-axis lies on $x$ y plane and $y z$. Therefore, its distance from $x y$ and $y z$ plane is 0 . $\therefore$ By the basic...

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If $\mathrm{l}_{1}, \mathrm{~m}_{1}, \mathrm{n}_{1}$ and $\mathrm{l}_{2}, \mathrm{~m}_{2}, \mathrm{n}_{2}$ are the direction cosines of two mutually perpendicular lines, show that the direction cosines of the line perpendicular to both of these are $\left(\mathrm{m}_{1} \mathrm{n}_{2}-\mathrm{m}_{2} \mathrm{n}_{1}\right),\left(\mathrm{n}_{1} \mathrm{l}_{2}-\mathrm{n}_{2} \mathrm{l}_{1}\right),\left(\mathrm{l}_{1} \mathrm{~m}_{2}-\mathrm{l}_{2} \mathrm{~m}_{1}\right)$

Solution: Let's consider $l, m, n$ be the direction cosines of the line perpendicular to each of the given lines. Therefore, $ll_{1}+m m_{1}+n n_{1}=0 \ldots(1)$ And...

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In the following cases, determine whether the given planes are parallel or perpendicular, and in case they are neither, find the angles between them.
(a) 7x + 5y + 6z + 30 = 0 and 3x – y – 10z + 4 = 0
(b) 2x + y + 3z – 2 = 0 and x – 2y + 5 = 0

Solution: (a) $7 x+5 y+6 z+30=0$ and $3 x-y-10 z+4=0$ It is given that The eq. of the given planes are $7 x+5 y+6 z+30=0$ and $3 x-y-10 z+4=0$ Two planes are $\perp$ if the direction ratio of the...

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Find the vector and Cartesian equations of the planes
(a) that passes through the point $(1,0,-2)$ and the normal to the plane is $\hat{i}+\hat{j}-\hat{k}$
(b) that passes through the point $(1,4,6)$ and the normal vector to the plane is $\hat{i}-2 \hat{j}+\hat{k}$

Solution: (a) That passes through the point $(1,0,-2)$ and the normal to the plane is $\hat{\mathrm{i}}+\hat{\mathrm{j}}-\hat{\mathrm{k}}$ Let's say that the position vector of the point $(1,0,-2)$...

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Find the shortest distance between the lines whose vector equations are $\vec{r}=(\hat{i}+2 \hat{j}+3 \hat{k})+\lambda(\hat{i}-3 \hat{j}+2 \hat{k})$ and $\vec{r}=4 \hat{i}+5 \hat{j}-6 \hat{k}+\mu(2 \hat{i}+3 \hat{j}+\hat{k})$

Solution: It is known to us that shortest distance between two lines $\vec{r}=\overrightarrow{a_{1}}+\lambda \overrightarrow{b_{1}}$ and $\vec{r}=\overrightarrow{a_{2}}+\mu \overrightarrow{b_{2}}$...

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Find the equation of the line in vector and in Cartesian form that passes through the point with position vector $2 \hat{\mathrm{i}}-\hat{\mathrm{j}}+4 \hat{\mathrm{k}}$ and $\hat{\mathrm{i}}+2 \hat{\mathrm{j}}-\hat{\mathrm{k}}$. is in the direction

Solution: Given: Vector equation of a line that passes through a given point whose position vector is $\vec{a}$ and parallel to a given vector $\vec{b}$ is $\vec{r}=\vec{a}+\lambda \vec{b}$ Let,...

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Consider the non-empty set consisting of children in a family and a relation R defined as aRb if a is brother of b. Then R is (A) symmetric but not transitive (B) transitive but not symmetric (C) neither symmetric nor transitive (D) both symmetric and transitive

The correct option is (B) transitive but not symmetric Given aRb β‡’ a is brother ofΒ b. This does not meanΒ bΒ is also a brother of a asΒ bΒ can be a sister ofΒ a. Therefore, R is not symmetric. aRb β‡’ a is...

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. Let \[\mathbf{A}\text{ }=\text{ }\left\{ \mathbf{1},\text{ }\mathbf{2},\text{ }\mathbf{3},\text{ }\ldots \text{ }\mathbf{9} \right\}\] and R be the relation in A Γ—A defined by (a, b) R (c, d) if a + d = b + c for (a, b), (c, d) in \[A\text{ }\times A\]. Prove that R is an equivalence relation and also obtain the equivalent class \[\left[ \left( \mathbf{2},\text{ }\mathbf{5} \right) \right]\].

Given, \[\mathbf{A}\text{ }=\text{ }\left\{ \mathbf{1},\text{ }\mathbf{2},\text{ }\mathbf{3},\text{ }\ldots \text{ }\mathbf{9} \right\}\]and (a, b) R (c, d) if a + d = b + c for \[\left( a,\text{ }b...

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Let R be relation defined on the set of natural number N as follows: \[\mathbf{R}\text{ }=\text{ }\{\left( \mathbf{x},\text{ }\mathbf{y} \right):\text{ }\mathbf{x}\in \mathbf{N},\text{ }\mathbf{y}\in \mathbf{N},\text{ }\mathbf{2x}\text{ }+\text{ }\mathbf{y}\text{ }=\text{ }\mathbf{41}\}\]. Find the domain and range of the relation R. Also verify whether R is reflexive, symmetric and transitive.

Given function: \[\mathbf{R}\text{ }=\text{ }\{\left( \mathbf{x},\text{ }\mathbf{y} \right):\text{ }\mathbf{x}\in \mathbf{N},\text{ }\mathbf{y}\in \mathbf{N},\text{ }\mathbf{2x}\text{ }+\text{...

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. If A = \[\left\{ \mathbf{1},\text{ }\mathbf{2},\text{ }\mathbf{3},\text{ }\mathbf{4}\text{ } \right\}\],define relations on A which have properties of being: (a) reflexive, transitive but not symmetric (b) symmetric but neither reflexive nor transitive (c) reflexive, symmetric and transitive.

According to the question, \[A\text{ }=\text{ }\left\{ 1,\text{ }2,\text{ }3 \right\}\]. (i) Let \[{{R}_{1}}~=\text{ }\left\{ \left( 1,\text{ }1 \right),\text{ }\left( 1,\text{ }2 \right),\text{...

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The domain of the function by f(x) = \[\mathbf{si}{{\mathbf{n}}^{-\mathbf{1}}}~\sqrt{\left( \mathbf{x}\text{ }\text{ }\mathbf{1} \right)}\] is (a) \[\left[ \mathbf{1},\text{ }\mathbf{2} \right]\] (b) \[\left[ -\mathbf{1},\text{ }\mathbf{1} \right]\] (c) \[\left[ \mathbf{0},\text{ }\mathbf{1} \right]\] (d) none of these

The correct option is Β (a) \[\left[ \mathbf{1},\text{ }\mathbf{2} \right]\] We know that, \[si{{n}^{-1}}~x\] is defined for \[x\in \left[ -1,\text{ }1 \right]\] So, f(x) =...

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Given the sets A = {1, 3, 5}, B = {2, 4, 6} and C = {0, 2, 4, 6, 8}, which of the following may be considered as universals set (s) for all the three sets A, B and C(i) {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10}(ii) {1, 2, 3, 4, 5, 6, 7, 8}

(i) A βŠ‚ {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10} B βŠ‚ {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10} C βŠ‚ {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10} As a result, the set {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10} is the universal set...

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