Question

若sin(a+B)=1/2,sin(a-B)=1/3,则tana/tanB等于多少?求详解,

Answer 1

sin(a+b)=1/2,sin(a-b)=1/3,则tana/tanb=?

sin(a+b)=sinacosb+cosasinb=1/2

sin(a-b)=sinacosb-cosasinb=1/3

联立--->sinacosb=5/12,cosasinb=1/12

相除--->tana/tanb=5