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MathsMediumMCQ2021 · 31 Aug Shift 2

Q62.The number of solutions of the equation 32tan2𝑥+ 32sec2𝑥= 81, 0 ≤𝑥≤ 𝜋 is : 4 (1) 0 (2) 2 (3) 1 (4) 3 JEE Main 2021 (31 Aug Shift 2) JEE Main Previous Year Paper 𝑧- 𝑖

What This Question Tests

This question tests the ability to simplify a trigonometric equation using identities, convert it into an exponential equation, and then solve for x within a specified interval.

Concepts Tested

Trigonometric identitiesExponential equationsQuadratic equationsDomain and range of trigonometric functions

Formulas Used

sec²x = 1 + tan²x

a^(m+n) = a^m * a^n

📚 NCERT Sections This Tests

11.8Light Of Frequency 7.21 × 1014 Hz Is Incident On A Metal Surface.

Physics Class 12 · Chapter 11

68% match

11.8 Light of frequency 7.21 × 1014 Hz is incident on a metal surface. Electrons with a maximum speed of 6.0 × 105 m/s are ejected from the surface. What is the threshold frequency for photoemission of electrons?

2.1Two Charges 5 × 10–8 C And –3 × 10–8 C Are Located 16 Cm Apart. At

Physics Class 11 · Chapter 2

68% match

2.1 Two charges 5 × 10–8 C and –3 × 10–8 C are located 16 cm apart. At what point(s) on the line joining the two charges is the electric potential zero? Take the potential at infinity to be zero.

9.17(A) Sin I¢C = 1.44/1.68 Which Gives I¢C = 59°. Total Internal Reflection

Physics Class 12 · Chapter 9

68% match

9.17 (a) sin i¢c = 1.44/1.68 which gives i¢c = 59°. Total internal reflection takes place when i > 59° or when r < rmax = 31°. Now, (sin i /sin r max max ) = 1.68 , which gives imax ~ 60°. Thus, all incident rays of angles in the range 0 < i < 60° will suffer total internal reflections in the pipe. (If the length of the pipe is finite, which it is in practice, there will be a lower limit on i determined by the ratio of the diameter to the length of the pipe.) (b) If there is no outer coating, i¢c = sin–1(1/1.68) = 36.5°. Now, i = 90° will have r = 36.5° and i¢ = 53.5° which is greater than i¢c. Thus, all incident rays (in the range 53.5° < i < 90°) will suffer total internal reflections.

📋 Question Details

Chapter
Trigonometric Functions & Equations
Topic
Solving trigonometric equations
Year
2021
Shift
31 Aug Shift 2
Q Number
Q62
Type
MCQ
NCERT Ref
Class 11 Mathematics Ch 3: Trigonometric Functions

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