Question

choose the correct option. justify your choice
(i) 9 sec2 A - 9 tan2 A =
A) 1 B) 9 C) 8 D) 0​

Answer 1

Answer:

9 Sec^2A - 9tan^2A

9(sec^2A- tan^2A)

9.1. [sec^2A-tan^2A= 1]

=9

Answer 2

ANSWER:

• The Value of above expression is 9

GIVEN:

• 9sec²A-9tan²A

TO FIND:

• Value of above expression.

SOLUTION:

= 9sec²A-9tan²A

= 9(sec²A-tan²A)

= 9*1. (Sec²Ø-tan²Ø = 1)

= 9

NOTE:

Some important formulas:

• Sin²Ø+Cos²Ø = 1
• 1+tan²Ø = Sec²Ø
• 1+Cot²Ø = Cosec²Ø

Trigonometric ratios :

• SinØ = Perpendicular/Hypotenuse
• CosØ = Base/Hypotenuse
• TanØ = Perpendicular/Base
• CotØ = Base/Perpendicular
• CosecØ = Hypotenuse/Perpendicular
• SecØ = Hypotenuse/Base