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questions
List of practice Questions
If the system of equations $kx + y + 2z = 1$, $3x - y - 2z = 2$, $-2x - 2y - 4z = 3$ has infinitely many solutions, then k is equal to ________
JEE Main - 2021
JEE Main
Mathematics
Linear Equations
Let A₁, A₂, A₃, … be squares such that for each n ≥ 1, the length of the side of $A_n$ equals the length of diagonal of $A_{n+1}$. If the length of $A_1$ is 12 cm, then the smallest value of n for which area of $A_n$ is less than one, is __________.
JEE Main - 2021
JEE Main
Mathematics
Sequences and Series
The number of points, at which the function f(x) = |2x + 1| - 3|x + 2| + |x² + x - 2|, x ∈ ℝ is not differentiable, is ________
JEE Main - 2021
JEE Main
Mathematics
Limits
The equation of the line through the point (0, 1, 2) and perpendicular to the line (x-1)/2 = (y+1)/3 = (z-1)/(-2) is:
JEE Main - 2021
JEE Main
Mathematics
3D Geometry
All possible values of θ ∈ [0, 2π] for which sin 2θ + tan 2θ>0 lie in :
JEE Main - 2021
JEE Main
Mathematics
Trigonometry
The total number of positive integral solutions (x, y, z) such that xyz=24 is :
JEE Main - 2021
JEE Main
Mathematics
Calculus
Angle of depression from tower top to A is 30°. After 20 seconds at B, it is 45°. Time taken from B to reach the base is :
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JEE Main
Mathematics
Height and Distance
Let α be the angle between the lines whose direction cosines satisfy the equations l + m - n = 0 and l² + m² - n² = 0. Then the value of sin⁴α + cos⁴α is :
JEE Main - 2021
JEE Main
Mathematics
3D Geometry
The integer k, for which the inequality x² - 2(3k-1)x + 8k² - 7>0 is valid for every x in ℝ, is :
JEE Main - 2021
JEE Main
Mathematics
Quadratic Equations
If Rolle's theorem holds for the function f(x) = x³ - ax² + bx - 4, x ∈ [1, 2] with f'(4/3) = 0, then ordered pair (a, b) is equal to :
JEE Main - 2021
JEE Main
Mathematics
Mean Value Theorem
The value of the integral ∫ sinθ sin2θ (sin⁶θ + sin⁴θ + sin²θ) / √(2sin⁴θ + 3sin²θ + 6) dθ is: (where c is a constant of integration)
JEE Main - 2021
JEE Main
Mathematics
Integration by Partial Fractions
Among the following, the number of halide(s) which is/are inert to hydrolysis is ___________: (A) BF$_3$, (B) SiCl$_4$, (C) PCl$_5$, (D) SF$_6$
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JEE Main
Chemistry
Periodicity of Elements
Which statement is correct ?
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JEE Main
Chemistry
Polymers
0.4 g mixture of NaOH, Na$_2$CO$_3$ and some inert impurities was first titrated with N/10 HCl using phenolphthalein as an indicator, 17.5 mL of HCl was required at the end point. After this methyl orange was added and titrated. 1.5 mL of same HCl was required for the next end point. The weight percentage of Na$_2$CO$_3$ in the mixture is _________
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JEE Main
Chemistry
Volumetric Analysis
A car tyre is filled with nitrogen gas at 35 psi at 27$^\circ$C. It will burst if pressure exceeds 40 psi. The temperature in $^\circ$C at which the car tyre will burst is ___________
JEE Main - 2021
JEE Main
Chemistry
States of matter
The major product of the following chemical reaction is : R-CN $\xrightarrow{(1) H_3O^+, \Delta (2) SOCl_2 (3) Pd/BaSO_4, H_2}$ ?
(Using $R$ as the alkyl group from the prompt skeleton)
JEE Main - 2021
JEE Main
Chemistry
Aldehydes And Ketones
Given below are two statements : Statement I : An allotrope of oxygen is an important intermediate in the formation of reducing smog. Statement II : Gases such as oxides of nitrogen and sulphur present in troposphere contribute to the formation of photochemical smog. In the light of the above statements, choose the correct answer from the options given below :
JEE Main - 2021
JEE Main
Chemistry
Environmental Chemistry
Complete combustion of 1.80 g of an oxygen containing compound (C$_x$H$_y$O$_z$) gave 2.64 g of CO$_2$ and 1.08 g of H$_2$O. The percentage of oxygen in the organic compound is :
JEE Main - 2021
JEE Main
Chemistry
Quantitative Analysis
In Freundlich adsorption isotherm at moderate pressure, the extent of adsorption $(x/m)$ is directly proportional to $P^x$. The value of x is :
JEE Main - 2021
JEE Main
Chemistry
Surface Chemistry
Ellingham diagram is a graphical representation of :
JEE Main - 2021
JEE Main
Chemistry
Metallurgy
Which of the following equation depicts the oxidizing nature of $H_2O_2$?
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JEE Main
Chemistry
Hydrogen
The correct statement about B$_2$H$_6$ is :
JEE Main - 2021
JEE Main
Chemistry
Periodicity of Elements
Given below are two statements : Statement I : CeO$_2$ can be used for oxidation of aldehydes and ketones. Statement II : Aqueous solution of EuSO$_4$ is a strong reducing agent. In the light of the above statements, choose the correct answer :
JEE Main - 2021
JEE Main
Chemistry
d And f - Block Elements
In which of the following pairs, the outer most electronic configuration will be the same ?
JEE Main - 2021
JEE Main
Chemistry
Classification of elements and periodicity in properties
The solubility of AgCN in a buffer solution of pH=3 is x. The value of x is : [Assume : No cyano complex is formed ; $K_{sp}(\text{AgCN}) = 2.2 \times 10^{-16}$ and $K_a(\text{HCN}) = 6.2 \times 10^{-10}$]
JEE Main - 2021
JEE Main
Chemistry
Ionic Equilibrium In Solution
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