Question

4, which of the Fallowing is defined ?
a). tan 90°
b), cot 0°
c) cosec90° d. Sec90°
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Answer 1

tan 90 = sin 90cos 90 = 10 is not defined

cot 0 = cos 0sin 0 = 10 is not defined

cosec 90 = 1sin 90 = 11 = 1

sec 90 = 1cos 90 = 10 is not defined

Thus, only cosec 90 is defined.

Answer 2

Cosec 90 is defined

Cosec 90 ----1

.------------------------------------------------------------------------

Tan 90 ----- infinite

Sec 90 --_--- infinite

Cot 0 ------- infinite