RD Sharma - Mathematics

Book: RD Sharma - Mathematics

Chapter: 7. Values of Trigonometric Functions at Sum of Difference of Angles

Subject: Maths - Class 11th

Q. No. 19 of MCQ

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19

Mark the correct alternative in the following:

If A – B = π /4, then (1 + tan A) (1 – tanB) is equal to



1+tan A tan B=tan A-tan B


tan A-tan B-tan A tan B=1


add both side 1


1+tan A-tan B-tan A tan B=1+1


(1+tan A)(1+tan B)=2


Case2:


put A=0 AND


(1+tan A )(1-tan A )=1× 2

Chapter Exercises

Exercise 7.1
Exercise 7.2
Very Short Answer
MCQ

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17

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18

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19

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