Question

Use cofunctions of complementary angles to evaluate.
csc(19°) = sec

Answer 1

cofunctions of complementary angles are:

● sin(x) = cos(90-x)
● cos(x) = sin(90-x)

● csc(x) = sec(90-x)
● sec(x) = csc(90-x)

●tan(x) = cot (90-x)
● cot(x) = tan(90-x)
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◆Given question:

csc (19°) = sec (90-19) = sec (71°)

Answer is sec (71°)