
sin,cos,α……你们的数学老师都怎么念这些符号?

cosαπ2sinα可以写成这样吗
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cos(a b)=?

a∈(0,π),0 sin a cos a 1 ∴a∈(π/2,π) 这一步是怎么推的?

=(cosbcosπ/4)-sinbsin π/4 =√2/2(cosb-sinb) =-√2/2(√2sinb-π
sin,cos,α……你们的数学老师都怎么念这些符号?
cosαπ2sinα可以写成这样吗
cos(a b)=?
a∈(0,π),0 sin a cos a 1 ∴a∈(π/2,π) 这一步是怎么推的?
=(cosbcosπ/4)-sinbsin π/4 =√2/2(cosb-sinb) =-√2/2(√2sinb-π