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CBSEGr 12 · Mathematics · Determinants

Determinant of a 3x3 Matrix: A Real-World Application?

Consider a rectangular garden with a length of 5 meters, a width of 4 meters, and a height of 3 meters. The area above the top 2 meters is irrigated using a pump. Given that the pump can pump out water at a rate of 0.25 cubic meters per minute, determine the time taken to dry the top 2 meters of the garden using the determinant of a 3x3 matrix to calculate the volume of the water to be pumped out.

💬 10
06 Sept
CBSEGr 12 · Mathematics · Relations and Functions

Can a function have multiple relationships?

Consider a relation R = {(1, 3), (2, 5), (3, 7)} and a function f(x) = 2x + 1. Can we define a function f(x) that satisfies the relation R, and if so, how would its graph look? Provide a detailed explanation.

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05 Sept
CBSEGr 12 · Mathematics · Vector Algebra

A Parallelogram Law Puzzle?

If two forces of magnitudes 6 N and 8 N act on a point, such that the triangle formed by these forces and their resultant is a right-angled triangle, determine the magnitude of the resultant force.

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04 Sept
CBSEGr 12 · Mathematics · Three Dimensional Geometry

Reflecting Points on a Plane?

Suppose you're given a plane defined by the equation 2x - 3y + 4z = 7. You have a point P in 3D space, and you need to reflect this point about this plane. Can you express the coordinates of the reflected point P' in terms of the coordinates of P?

💬 10
04 Sept
CBSEGr 12 · Mathematics · Inverse Trigonometric Functions

Tangent Divergence?

Consider a right-angled triangle ABC with a right angle at B. For what value of angle A, will the tangent of angle A be greater than the angle itself?

💬 10
02 Sept
CBSEGr 12 · Mathematics · Linear Programming

Maximising Profit with Resource Constraints?

A factory produces two products, A and B, using two resources, Labour and Machinery. Product A requires 3 units of Labour and 2 units of Machinery per unit produced, while Product B requires 2 units of Labour and 4 units of Machinery per unit produced. The factory has a maximum of 150 units of Labour and 200 units of Machinery available daily. Formulate a linear programming problem to maximise the total profit, which is ₹10 per unit of Product A and ₹15 per unit of Product B.

💬 10
30 Aug
CBSEGr 12 · Mathematics · Relations and Functions

Function Composition Puzzle?

Consider two functions f(x) = 2x^2 and g(x) = √x. If the composite function (f ∘ g)(x) is equivalent to x^(4/3), then determine the range of values for x such that the composite function is defined.

💬 10
30 Aug
CBSEGr 12 · Mathematics · Differential Equations

Population Growth Modelling

The population of a town is modelled by the logistic differential equation dP/dt = 0.04P(1 - P/2000), where P is the population in thousands. Assuming a constant birth rate and no deaths, derive an expression for the population after 5 years if the initial population is 500 people. Explain your reasoning and provide a valid mathematical expression.

💬 10
30 Aug
CBSEGr 12 · Mathematics · Determinants

Finding the Inverse of a 3x3 Determinant?

Given a 3x3 matrix A with a non-zero determinant, prove that the inverse of A exists if and only if the determinant of A is non-zero. Can you provide a 2x2 submatrix within A that has a non-zero determinant?

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26 Aug
CBSEGr 12 · Mathematics · Application of Derivatives

Maximizing Profit in Industry?

A smartphone manufacturing company produces x units of its latest model in a day. The cost price of each unit is ₹150 and the selling price is ₹250. Using the concept of optimization, determine the production level that maximizes profit, assuming the cost and selling price remain constant.

💬 10
23 Aug
CBSEGr 12 · Mathematics · Matrices

Transformation Matrix?

Consider a transformation matrix A that represents a rotation of 45° in the clockwise direction followed by a reflection across the line y = x. If the matrix for this transformation is given by A = egin{bmatrix} a & b \ c & d \ ext{end{bmatrix}}, what can you infer about the values of a, b, c, and d?

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22 Aug
CBSEGr 12 · Mathematics · Three Dimensional Geometry

Distance Between Two Skew Lines?

In a 3D space, consider two skew lines L1 and L2, each with direction cosines (1/√3, 1/√3, 1) and (-1/√3, -1/√3, 1) respectively. Given the point P (2, 3, 4) lies on L1, determine the shortest distance between L1 and L2.

💬 10
22 Aug
CBSEGr 12 · Mathematics · Application of Integrals

Average Rainfall: A Complex Analysis?

A region experiences an average rainfall of 400 mm/year, distributed evenly across 12 months. The rainfall is heavily dependent on the two monsoon seasons, with 60% of the total rainfall occurring during these periods. If the rainfall during the monsoon seasons is uniformly distributed, determine the monthly rainfall during these seasons.

💬 10
21 Aug
CBSEGr 12 · Mathematics · Integrals

Finding the Volume of a Solid of Revolution?

A water tank is in the shape of a right circular cone with a height of 10 m and a base radius of 4 m. If water is poured into the tank at a rate of 0.5 m^3/min, how long will it take for the tank to be filled if the water level is rising at a rate of 1/5 of the radius with respect to the height of the water?

💬 10
21 Aug
CBSEGr 12 · Mathematics · Application of Derivatives

Maximizing a Profit Function?

A company manufactures and sells two products, A and B. The profit function, P, in terms of the number of units produced of each product, x and y, is given by P(x,y) = 100x - 2y + 2xy - 1000. A factory has a fixed constraint that the number of units produced of product B cannot exceed double the number of units produced of product A, i.e., y ≤ 2x. What should be the production levels of product A and product B to maximize the profit function under this constraint?

💬 10
20 Aug
CBSEGr 12 · Mathematics · Integrals

Deflection of a Beam?

A 2m long, 0.1m wide beam is deflected by 0.05m under a mass of 50kg at its midpoint. Given that the cross-sectional area of the beam is uniform, derive a mathematical expression for the deflection 'y' at any point 'x' from the load, using the equation of the integral of moment of the beam's section.

💬 10
19 Aug
CBSEGr 12 · Mathematics · Matrices

Matrix Transformation Puzzle?

Rahul is given a matrix transformation T: ℝ² → ℝ² defined by the matrix ┌ 1 -3 ┐ ┌ 4 2 ┐ ┌ 2 1 ┐ Where the first row represents transformation of x-axis and the second row represents transformation of y-axis. Can you describe the effect of applying transformation T on the point (a, b)?

💬 10
19 Aug
CBSEGr 12 · Mathematics · Continuity and Differentiability

Differentiability at Critical Points?

A function f(x) = |x^2 - 4| is known to be differentiable everywhere except at its critical points. Prove your answer based on Rolle's theorem.

💬 10
18 Aug
CBSEGr 12 · Mathematics · Application of Integrals

Evaluating Total Revenue?

A company produces and sells x units of a product. The revenue generated per unit is given by the function R(x) = 3x^2 + 5x - 4. Evaluate the total revenue generated from the sale of the first 500 units of the product. Consider the revenue generated from the first 400 units, and then from the next 100 units separately, to validate your approach.

💬 10
17 Aug
CBSEGr 12 · Mathematics · Inverse Trigonometric Functions

Inverse Trigonometric Functions: A Real-World Conundrum?

A surveyor measures the angle between a straight line and the tangent to a curve. The angle is found to be 36.87°. If the surveyor has an inverse trigonometric function calculator, which inverse trigonometric function should she use to find the acute angle between the line and the normal to the curve, assuming the angle is bisected?

💬 10
17 Aug
CBSEGr 12 · Mathematics · Application of Integrals

Mass Calculation of a Spherical Shell?

A spherical shell is being manufactured with an inner radius of 12 cm and an outer radius of 18 cm. The shell is to be made of a material with a density of 0.6 g/cm³. Calculate the mass of the shell, given that it requires 0.2 kg of paint to cover its surface.

💬 10
16 Aug
CBSEGr 12 · Mathematics · Differential Equations

Solving the Logistic Growth Equation?

The population of a city is growing according to the logistic growth equation dP/dt = kP(1 - P/M), where P is the population, k is the growth rate, and M is the carrying capacity. If the initial population is 10,000 and the carrying capacity is 10 million, can the city's population reach 1 million in 10 years?

💬 10
15 Aug
CBSEGr 12 · Mathematics · Relations and Functions

Can we be functionally equivalent?

Suppose f(x) = 3x + 2 and g(x) = 2x + 4 are two functions defined for all real numbers. Can we say that f(x) and g(x) are the same function, even though their equations look different?

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14 Aug
CBSEGr 12 · Mathematics · Application of Integrals

Modeling Pollution in a River?

The level of pollution in a river is given by the concentration of pollutants (in kg/m) along its length (in km). The river is 10 km long and the concentration of pollutants is 4 kg/m at the source and 2 kg/m at the point of discharge. Assuming the concentration decreases linearly along the river length, find the total amount of pollutants in the river using integration.

💬 10
14 Aug
CBSEGr 12 · Mathematics · Determinants

Inverse of a Matrix?

Given two invertible 2x2 matrices A and B, if AB = C, is it always true that (AB)^-1 = B^-1A^-1? Justify your answer with a suitable example.

💬 10
14 Aug
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