02 Inverse Trigonometric Functions
Exercise 01
Question:
Find the principal value of cot−1(√3).
Answer:
Answer: Step 1: Recall that cot−1(x) is the inverse of cot(x).
Step 2: Recall that cot(x) = cos(x)/sin(x).
Step 3: Substitute √3 for x in the equation cot(x) = cos(x)/sin(x).
Step 4: Solve for cos(x)/sin(x) = √3.
Step 5: Recall that cos(x) = sin(90° - x).
Step 6: Substitute 90° - x for cos(x) in the equation sin(90° - x)/sin(x) = √3.
Step 7: Solve for sin(90° - x)/sin(x) = √3.
Step 8: Recall that sin(90° - x) = cos(x).
Step 9: Substitute cos(x) for sin(90° - x) in the equation cos(x)/sin(x) = √3.
Step 10: Solve for cos(x)/sin(x) = √3.
Step 11: Recall that cot-1(x) is the inverse of cot(x).
Step 12: Substitute the value obtained in Step 10 for x in the equation cot-1(x).
Step 13: The principal value of cot−1(√3) is 60°.
Question:
Find the principal value of sec−1(2/√3).
Answer:
Step 1: Find the inverse of secant.
The inverse of secant is cosecant, which is written as csc or cosec.
Step 2: Substitute the given value in the cosecant equation.
csc^−1(2/√3)
Step 3: Solve for the principal value.
The principal value of csc−1(2/√3) is 60°.
Question:
Find the principal value of cos−1(√3/2)
Answer:
Answer: Step 1: Convert √3/2 into a decimal by dividing 3 by 2.
Answer: 1.5
Step 2: Calculate the inverse cosine of 1.5.
Answer: The principal value of cos−1(√3/2) is 60°.
Question:
Find the principal value of tan−1(−√3).
Answer:
Step 1: Recall that tan−1(x) is the inverse of the tangent function, which is equal to the angle whose tangent is equal to x.
Step 2: Since tan−1(−√3) is the angle whose tangent is equal to -√3, we can use a trigonometric identity to solve for the angle.
Step 3: The identity we will use is tan(α) = -√3, where α is the angle we are trying to find.
Step 4: Solving for α, we get α = tan−1(-√3).
Step 5: The principal value of tan−1(−√3) is -60°.
Question:
Find the principal value of cos−1(−1/√2)
Answer:
Answer:
- cos^-1(x) is the inverse cosine function, which is also known as the arccosine function.
- To find the principal value of cos−1(-1/√2), we need to calculate the arccosine of -1/√2.
- Using a calculator, we can find that the arccosine of -1/√2 is equal to 3π/4.
- Therefore, the principal value of cos−1(-1/√2) is 3π/4.
Question:
Find the principal value of cosec−1(2).
Answer:
Step 1: Recall that cosec−1(x) is the inverse of cosec(x).
Step 2: Recall that cosec(x) = 1/sin(x).
Step 3: Set 1/sin(x) = 2.
Step 4: Solve for x by taking the inverse sine of both sides.
Step 5: The principal value of cosec−1(2) is π/3 radians.
Question:
Find the value of tan−1(1)+cos−1(−1/2)+sin−1(−1/2).
Answer:
Step 1: tan−1(1) = π/4
Step 2: cos−1(−1/2) = 3π/4
Step 3: sin−1(−1/2) = -π/2
Step 4: Add the three values together: π/4 + 3π/4 + (-π/2) = π/2
Therefore, the value of tan−1(1)+cos−1(−1/2)+sin−1(−1/2) is π/2.
Question:
Find the principal value of cos−1(−1/2).
Answer:
Step 1: Recall that the principal value of cos−1(x) is the angle θ in the interval [0, 2π] such that cos(θ) = x.
Step 2: We are given that x = −1/2.
Step 3: Solve the equation cos(θ) = −1/2 to find θ.
Step 4: Using a calculator or a table of values, we find that θ = 2.094395102393195 radians.
Step 5: Therefore, the principal value of cos−1(−1/2) is 2.094395102393195 radians.
Question:
Find the principal value of sin−1(−1/2)
Answer:
Step 1: Recall that sin−1(x) is the inverse of the sine function, which is also known as the arcsin function.
Step 2: Use the arcsin function to find the principal value of -1/2.
Step 3: The principal value of sin−1(-1/2) is -π/6.
Question:
Find the principal value of cosec−1(−√2)
Answer:
Answer: Step 1: Recall that cosec−1(x) = arcsin(1/x)
Step 2: Substitute -√2 for x in the equation: cosec−1(-√2) = arcsin(1/(-√2))
Step 3: Simplify the expression: cosec−1(-√2) = arcsin(-1/√2)
Step 4: Use a calculator to find the principal value of arcsin(-1/√2): cosec−1(-√2) = -π/4
Question:
Find the value of cos−1(1/2)+2sin−1(1/2)
Answer:
Given, cos−1(1/2) + 2sin−1(1/2)
Step 1: Calculate the value of cos^−1(1/2)
cos−1(1/2) = 60°
Step 2: Calculate the value of sin−1(1/2)
sin−1(1/2) = 30°
Step 3: Substitute the values in the given equation.
60° + 2(30°) = 120°
Hence, the value of cos−1(1/2) + 2sin−1(1/2) = 120°.
Question:
Find the value of tan−1 √3 −sec−1(−2) is equal to A π B −π/3 C 3π D 2π/3
Answer:
Answer: B -π/3
Question:
Find the principal value of tan−1(−1).
Answer:
Step 1: Recall that the principal value of tan−1(x) is the angle measured in the counterclockwise direction from the positive x-axis to the ray from the origin that intersects the point (x,y).
Step 2: In this case, x = -1, so the principal value of tan−1(-1) is the angle measured in the counterclockwise direction from the positive x-axis to the ray from the origin that intersects the point (-1,y).
Step 3: Since y = -1, the principal value of tan−1(-1) is the angle measured in the counterclockwise direction from the positive x-axis to the ray from the origin that intersects the point (-1,-1).
Step 4: Therefore, the principal value of tan−1(-1) is π radians or 180°.
JEE NCERT Solutions (Mathematics)
01 Relations and Functions
02 Inverse Trigonometric Functions
03 Matrices
04 Determinants
05 Continuity and Differentiability
- Exercise 01
- Exercise 02
- Exercise 03
- Exercise 04
- Exercise 05
- Exercise 06
- Exercise 07
- Exercise 08
- Miscellaneous Exercises
06 Application of Derivatives
07 Integrals
08 Application of Integrals
09 Vectors
10 Three Dimensional Geometry
11 Linear Programming
12 Probability