Question

Q. 2. For A 30°, verify that cos 2A= 1-tan³A 1+tan²A​

Answer 1

Answer:

evaluate 1) [(-¾)-²]²2) [(⅗)²]-²

2) [(⅗)²]-²

evaluate 1) [(-¾)-²]²

Answer 2

Step-by-step explanation:

hlo mate here's your answer

If

A=

30 0

,

To prove,

cos2A=

1 + tan 2 A

1 − tan 2 A

Put

A=

30 o

in L.H.S, we get

=

cos

60

0

=

2

1

cos2A=

cos2 (

30

o

)

Also, put

A=

30 o

in R.H.S,

1 + tan 2 A

1 − tan 2 A

=

1 + tan 2 30 o

1 − tan 2 30 o

=

1 + (

3

1

) 2

1 − (

3

1

) 2

⇒

1+

3

1

1−

3

1

→

3 + 1

3 − 1

=

4

2

=

2

1

L.H.S= R.H.S=

2

1

Hence proved.

I hope its help you mark as brainlist plz