WBJEE · Maths · Three Dimensional Geometry
Angle between two diagonals of a cube will be
- A \(\cos ^{-1}\left(\frac{1}{3}\right)\)
- B \(\sin ^{-1}\left(\frac{1}{3}\right)\)
- C \(\frac{\pi}{2}-\cos ^{-1}\left(\frac{1}{3}\right)\)
- D \(\frac{\pi}{2}-\sin ^{-1}\left(\frac{1}{3}\right)\)
Answer & Solution
Correct Answer
(A) \(\cos ^{-1}\left(\frac{1}{3}\right)\)
Step-by-step Solution
Detailed explanation
d.c. of diagonal \(\mathrm{OC}: \frac{1}{\sqrt{3}}, \frac{1}{\sqrt{3}}, \frac{1}{\sqrt{3}}\) or, \(-\frac{1}{\sqrt{3}},-\frac{1}{\sqrt{3}},-\frac{1}{\sqrt{3}}\) d.c. of diagonal AD : \(-\frac{1}{\sqrt{3}}, \frac{1}{\sqrt{3}}, \frac{1}{\sqrt{3}}\) or,…
See the Complete Solution
Get step-by-step explanations for this and 2.5 Lakh+ more JEE, NEET & CET questions.
- Unlock all solutions
- Practice the full chapter
- Track accuracy across PYQs
4.8 rated on Google Play · 14,000+ reviews
More questions from Maths
- A line cuts the \(X\) -axis at \(A(5,0)\) and the \(Y\) -axis at \(B(0,-3)\). A variable line \(P Q\) is drawn perpendicular to \(A B\) cutting the \(X\) -axis at \(P\) and the \(Y\) -axis at \(Q\). If \(A Q\) and \(B P\) meet at \(R\), then the locus of \(R\) isWBJEE 2018 Hard
- \(\int \frac{\log \sqrt{x}}{3 x} d x\) is equal toWBJEE 2016 Medium
- Let \(\cos ^{-1}\left(\frac{y}{b}\right)=\log _e\left(\frac{x}{n}\right)^n\), then \(A y_2+B y_1+C y=0\) is possible forWBJEE 2023 Hard
- The digit in the unit's place of the number \(1 !+2 !+3 !+\ldots \ldots \ldots+99 !\) isWBJEE 2021 Easy
- If \(\left(x^2 \log _x 27\right) \cdot \log _9 x=x+4\) then the value of \(x\) isWBJEE 2024 Easy
- Let \(f: R \rightarrow R\) be a twice continuously differentiable function such that \(f(0)=f(1)=f^{\prime}(0)=0 .\) ThenWBJEE 2018 Easy
More PYQs from WBJEE
- The maximum value of \(|x|\), when the complex number \(z\) satisfies the condition \(\left|z+\frac{2}{z}\right|=2\) isWBJEE 2012 Hard
- If \(\int e^{\sin x} \cdot\left[\frac{x \cos ^{3} x-\sin x}{\cos ^{2} x}\right] d x=e^{\sin x} f(x)+c\)
where c is constant of integration, then \(f(x)\) is
equal toWBJEE 2018 Medium - Let \(A\) and \(B\) be two square matrices of order 3 and \(A B=O_{3}\), where \(O_{3}\) denotes the null matrix of order 3. Then,WBJEE 2019 Easy
- Ionisation potential values of noble gases decrease down the group with increase in atomic size. Xenon forms binary fluorides by the direct reaction of elements. Identify the correct statement(s) from below.WBJEE 2015 Easy
- The value of \(\lim _{n \rightarrow \infty}\left[\frac{n}{n^2+1^2}+\frac{n}{n^2+2^2}+\ldots \ldots . . \frac{n}{n^2+n^2}\right]\) isWBJEE 2009 Medium
- Two positive charges \(Q\) and \(4 Q\) are placed at points \(A\) and \(B\) respectively, where \(B\) is at a distance \(d\) units to the right of \(A\). The total electric potential due to these charges is minimum at \(P\) on the line through \(A\) and \(B\). What is (are) the distance (s) of \(P\) from \(A ?\)WBJEE 2018 Medium