Respuesta :

Answer:

(i) 12.25

(ii) 12.25.

Step-by-step 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.