Question

[Thai Nguyen]

a) Sắp xếp theo thứ tự tăng dần: \(\sin47^o13;\cos72^o20;\sin55^o25;\cos44^o30\)

b) Tính: \(2017.\sin^223^o+\sin^237^o+\sin^253^o+2017.\sin^267^o\)

Answer 1

[Nguyễn Lê Phước Thịnh]

a: \(sin17^040'< sin45^030'< sin47^013'< sin55^025'\)

nên \(cos72^020'< cos44^030'< sin47^013'< sin55^025'\)

b: \(=2017\left(sin^223^0+sin^267^0\right)+\left(sin^237^0+sin^253^0\right)\)

=2017+1

=2018