Answer:
(i) 12.25
(ii) 12.25.
Explanation:
(1) cot^2 O = (7/2)^2 = 49/4
= 12.25.
(2) (1 - sin O) ( 1 + sin O) 1 - sin^2 O cos^2 O
---------------------------- = ------------- = --------------
(1 - cos O)(1 + cos O) 1 - cos^2 O 1 - cos^2 O
As cot O = 2/7, tan O = 1 /2/7 = 7/2.
Hypotenuse of the right triangle = √( 2^2 + 7^2)
= √53
So cos O = 7/√53
Therefore the original function = cos^2 O / (1 - cos^2 O)
= (7/√53)^2 / (1 - (7/√53)^2 )
= 49/53 / 4/53
= 49/4.