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questions
List of practice Questions
If
\[ \begin{pmatrix} 2 & 1 \\ 3 & 2 \end{pmatrix} \cdot A \cdot \begin{pmatrix} -3 & 2 \\ 5 & -3 \end{pmatrix} = \begin{pmatrix} 1 & 0 \\ 0 & 1 \end{pmatrix}, \]
then \(A\) is:
WBJEE - 2024
WBJEE
Mathematics
Matrices and Determinants
Let
\[ f(x) = \begin{vmatrix} \cos x & x & 1 \\ 2 \sin x & x^3 & 2x \\ \tan x & x & 1 \end{vmatrix}, \]
then
\[ \lim_{x \to 0} \frac{f(x)}{x^2} = ? \]
WBJEE - 2024
WBJEE
Mathematics
Limits
In \(\mathbb{R}\), a relation \(p\) is defined as follows: For \(a, b \in \mathbb{R}\), \(apb\) holds if \(a^2 - 4ab + 3b^2 = 0\).
Then:
WBJEE - 2024
WBJEE
Mathematics
Relations and Functions
Let \(f : \mathbb{R} \to \mathbb{R}\) be a function defined by \(f(x) = \frac{e^{|x|} - e^{-x}}{e^x + e^{-x}}\), then:
WBJEE - 2024
WBJEE
Mathematics
Relations and Functions
Let A be the set of even natural numbers that are<8 and B be the set of prime integers that are<7. The number of relations from A to B is:
WBJEE - 2024
WBJEE
Mathematics
Relations and Functions
If \((1 + x + x^2 + x^3)^5 = \sum_{k=0}^{15} a_k x^k\), then \(\sum_{k=0}^{7} (-1)^k \cdot a_{2k}\) is equal to:
WBJEE - 2024
WBJEE
Mathematics
Binomial theorem
If \(z_1\) and \(z_2\) be two roots of the equation \(z^2 + az + b = 0, \, a^2 < 4b\), then the origin, \(z_1\) and \(z_2\) form an equilateral triangle if:
WBJEE - 2024
WBJEE
Mathematics
Complex numbers
If \((x^2 \log x) \log_9 x = x + 4\), then the value of \(x\) is:
WBJEE - 2024
WBJEE
Mathematics
Quadratic Equation
Let N be the number of quadratic equations with coefficients from {0,1,2,...,9} such that 0 is a solution of each equation. Then the value of N is:
WBJEE - 2024
WBJEE
Mathematics
Quadratic Equation
Let \(y = f(x)\) be any curve on the X-Y plane and \(P\) be a point on the curve. Let \(C\) be a fixed point not on the curve. The length \(PC\) is either a maximum or a minimum. Then:
WBJEE - 2024
WBJEE
Mathematics
Limits
If a particle moves in a straight line according to the law \(x = a \sin(\sqrt{t} + b)\), then the particle will come to rest at two points whose distance is:
WBJEE - 2024
WBJEE
Mathematics
Differential Equations
If for the series \(a_1, a_2, a_3, \ldots\), etc., \(a_{n+1} - a_n\) bears a constant ratio with \(a_n + a_{n+1}\), then \(a_1, a_2, a_3, \ldots\) are in:
WBJEE - 2024
WBJEE
Mathematics
Sequence and series
The value of the surface integral
\(\displaystyle\oiint_{s}zdxdy\)
where S is the external surface of the sphere x
2
+ y
2
+ z
2
= R
2
is
GATE Metallurgy - 2024
GATE Metallurgy
Engineering Mathematics
Vector identities
An infinite slope is made up of cohesionless soil with seepage parallel to and up to the sloping surface. The angle of slope is 30Β° with respect to horizontal ground surface. The unit weights of the saturated soil and water are 20 kN/m
3
and 10 kN/m
3
, respectively.
The minimum angle of shearing resistance of the soil (in degrees) for the critically stable condition of the slope is _____ (rounded off to the nearest integer).
GATE CE - 2024
GATE CE
Geotechnical Engineering
Shear Strength
The compound(s) which on reaction with CH
3
MgBr followed by treatment with aqueous NH
4
Cl would produce 1-methyl-1-phenylethanol as the major product is/are
IIT JAM CY - 2024
IIT JAM CY
Organic Chemistry
Reaction Mechanisms & Synthesis
The suitable synthetic route(s) for the following transformation
is/are
IIT JAM CY - 2024
IIT JAM CY
Organic Chemistry
Reaction Mechanisms & Synthesis
B
2
and C
2
, respectively, are
IIT JAM CY - 2024
IIT JAM CY
Physical Chemistry
Molecular structure and Chemical bonding
ZnβC bond polarity in the compounds below
follows the order
IIT JAM CY - 2024
IIT JAM CY
Inorganic Chemistry
Chemical bonding and molecular structure
The number and nature of dβd transition(s) in the case of Sc
2+
in an octahedral crystal field, respectively, are
[Ignore spin-orbit coupling and Jahn-Teller distortion.]
IIT JAM CY - 2024
IIT JAM CY
Inorganic Chemistry
d block elements
A system undergoes one clockwise cycle from point X back to point X as shown in the figure below:
The correct statement about this process is
IIT JAM CY - 2024
IIT JAM CY
Physical Chemistry
Thermodynamics
If nitrogen and oxygen gases are at the same temperature, the correct statement according to the kinetic theory of gases is
IIT JAM CY - 2024
IIT JAM CY
Physical Chemistry
Gaseous State
Consider photoelectric effect. The number of incident photons is the same for all frequencies. The plot that best describes the dependence of the number of photoelectrons (n) emitted as a function of the incident light frequency (Ξ½) is
IIT JAM CY - 2024
IIT JAM CY
Physical Chemistry
Atomic Structure
In the cell reaction
P
+
(ππ)+Q(π )βP(π )+Q
+
(ππ)
the EMF of the cell, πΈ
ππππ
is zero. The standard EMF of the cell, πΈ
π
ππππ
is
[Given:
Activities of all solids are unity.
Activity of P
+
(ππ) is 2 M. Activity of Q
+
(ππ) is 1 M.
π = universal gas constant; π = temperature; πΉ = Faraday constant]
IIT JAM CY - 2024
IIT JAM CY
Physical Chemistry
Electrochemistry
The major product formed in the following reaction
is
IIT JAM CY - 2024
IIT JAM CY
Organic Chemistry
Reaction Mechanisms & Synthesis
The major product formed in the following reaction
|
is
IIT JAM CY - 2024
IIT JAM CY
Organic Chemistry
Reaction Mechanisms & Synthesis
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