1
WB JEE 2025
MCQ (Single Correct Answer)
+1
-0.25
Change Language

The value of the expression ${ }^{47} C_4+\sum\limits_{j=1}^5{ }^{52-j} C_3$ is

A
${ }^{52} C_3$
B
${ }^{51} C_4$
C
${ }^{52} C_4$
D
${ }^{51} C_3$
2
WB JEE 2025
MCQ (Single Correct Answer)
+1
-0.25
Change Language

If $\operatorname{adj} B=A,|P|=|Q|=1$, then $\operatorname{adj}\left(Q^{-1} B P^{-1}\right)=$

A
$P Q$
B
$Q A P$
C
$P A Q$
D
$P A^{-1} Q$
3
WB JEE 2025
MCQ (Single Correct Answer)
+1
-0.25
Change Language

Let $\vec{a}, \vec{b}$ and $\vec{c}$ be vectors of equal magnitude such that the angle between $\vec{a}$ and $\vec{b}$ is $\alpha, \vec{b}$ and $\vec{c}$ is $\beta$ and $\vec{c}$ and $\vec{a}$ is $\gamma$. Then the minimum value of $\cos \alpha+\cos \beta+\cos \gamma$ is

A
$\frac{1}{2}$
B
$-\frac{1}{2}$
C
$\frac{3}{2}$
D
$-\frac{3}{2}$
4
WB JEE 2025
MCQ (Single Correct Answer)
+1
-0.25
Change Language

Let $f(x)$ be a second degree polynomial. If $f(1)=f(-1)$ and $p, q, r$ are in A.P., then $f^{\prime}(p), f^{\prime}(q), f^{\prime}(r)$ are

A
in A.P.
B
in G.P.
C
in H.P.
D
neither in A.P. or G.P. or H.P.
EXAM MAP