1
WB JEE 2026
MCQ (Single Correct Answer)
+1
-0.25
Change Language

The general solution of the equation $\sin ^{100} \mathrm{x}-\cos ^{100} \mathrm{x}=1$ is

A

$\left\{2 n \pi+\frac{\pi}{3}: n \in I\right\}$

B

$\left\{n \pi+\frac{\pi}{4}: n \in I\right\}$

C

$\left\{n \pi \pm \frac{\pi}{2}: n \in I\right\}$

D

$\left\{2 \mathrm{n} \pi-\frac{\pi}{3}: \mathrm{n} \in \mathrm{I}\right\}$

2
WB JEE 2026
MCQ (Single Correct Answer)
+1
-0.25
Change Language

If $\vec{a}=\hat{i}+\hat{j}+\hat{k}, \vec{b}=\hat{i}-\hat{j}+\hat{k}, \vec{c}=\hat{i}+2 \hat{j}-\hat{k}$, then the value of $\left|\begin{array}{lll}\vec{a} \cdot \vec{a} & \vec{a} \cdot \vec{b} & \vec{a} \cdot \vec{c} \\ \vec{b} \cdot \vec{a} & \vec{b} \cdot \vec{b} & \vec{b} \cdot \vec{c} \\ \vec{c} \cdot \vec{a} & \vec{c} \cdot \vec{b} & \vec{c} \cdot \vec{c}\end{array}\right|$ is equal to

A

64

B

0

C

14

D

16

3
WB JEE 2026
MCQ (Single Correct Answer)
+1
-0.25
Change Language

Number of elements in the range set of $f(x)=\left[\frac{x}{15}\right]\left[-\frac{15}{x}\right]$, for all $x \in(0,90$ ); (where [.] denotes the greatest integer function) is

A

8

B

7

C

6

D

5

4
WB JEE 2026
MCQ (Single Correct Answer)
+1
-0.25
Change Language

Let 10 Bags $B_1, B_2, \ldots, B_{10}$ which contains $21,22, \ldots, 30$ different articles respectively. Then the total number of ways to bring out 10 articles from a Bag is

A

${ }^{31} \mathrm{C}_{20}+{ }^{21} \mathrm{C}_{10}$

B

${ }^{31} \mathrm{C}_{20}-{ }^{21} \mathrm{C}_{10}$

C

${ }^{30} \mathrm{C}_{20}-{ }^{20} \mathrm{C}_{10}$

D

${ }^{30} \mathrm{C}_{20}+{ }^{20} \mathrm{C}_{10}$