Answer:The first one 18in.2
Step-by-step explanation:
Answer:
20 students are sitting in the library
Step-by-step explanation:
4 · 5 = 20
Given that
3 cos 80° cosec 10° + 2 sin 59° sec 31°
⇛3 cos(90°-10°) cosec 10°+2 sin (90°-31°) sec 31°
We know that
sin (90° - A) = cos A
cos (90°-A) = sin A
⇛3 sin 10° cosec 10° + 2 cos 31° sec 31°
⇛3 sin 10° (1/sin 10°) + 2 cos 31° (1/cos 31°)
⇛3 (sin 10°/sin 10°) + 2 (cos 31°/cos 31°)
⇛3 (1) + 2(1)
⇛3+2
⇛5
<u>Answer</u><u>:</u> Therefore, 3cos 80°cosec 10°+2cos 59°sec 31° = 5.
<u>also</u><u> read</u><u> similar</u><u> questions</u><u>:</u> (sin teta + sec teta)^ + (cos teta+ cosec teta )^ = (1 + sec x cosec)^
brainly.com/question/87846?referrer
I think it C
have a great day!!!