Question

cosa/tana.sina=16 then prove that seca=root17/4​

Answer 1

Step-by-step explanation:

•As sec

2

A−tan

2

A=1⇒secA=±

tan

2

A+1

=±

16

9

+1

=±

16

25

=±

4

5

⇒cosA=

secA

1

=±

5

4

And sin

2

A+cos

2

A=1

⇒sinA=±

1−cos

2

A

=±

1−

25

16

=±

25

9

=±

5

3

⇒sinAcosA=

25

12