Page 37 - Mathematics Class - XI

Case-Study Based Questions
Case-Study Based Questions
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1. In a class test of class - XI, teacher asked to students to consider A + B = . Where A and B both are
acute angles. 4

Based upon the above information, answer the following questions.
(a) Find the value of (1 + tan A) (1 + tan B)

(b) Find the value of (cot A – 1) (cot B – 1)
(c) Find the value of sin (A + B) – cos (A – B) + tan (A + B)

(d) Prove that tan A 1 tan B
1 tan B

2. In a class - XI, teacher assign a task to the students that cos 4 and cos 12 , q and φ both are
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located in IV quadrant then on the basis of above data, answer the following questions.

(a) cos( (b) sin( (c) tan(

Assertion-Reason Based Questions
Assertion-Reason Based Questions
Directions for Questions 1 to 3: In each of the questions given below, there are two statements marked as
Assertion (A) and Reason (R). Mark your answer as per the codes provided below:
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) A is false but R is true.

Q. 1. Assertion (A) : The measure of rotation of a given ray about its initial point is called an angle.
Reason (R) : The point of rotation is called a vertex.

Q. 2. Assertion (A) : Cosec x is negative in third and fourth quadrants.
Reason (R) : Cot x decreases from 0 to in first quadrant and increases from 0 to ∞ in third
quadrant.
Q. 3. Assertion (A) : Area of unit circle is p unit .
2
121p
Reason (R) : Radian measure of 40° 20' is equal to radian.
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Answers

Case-Study Based Questions: 1. (a) 2 (b) 2 (c) 1

2. (a) 33 (b) −16 (c) −56
65 65 33
Assertion-Reason Based Questions: 1. (b) 2. (c) 3. (b)

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