Question

cos(40°+A)=sin30°,then A=​

Answer 1

Answer:

20 , 260

Step-by-step explanation:

Since sin 30 = cos 60 = cos 300 = 1/2

A + 40 = 60     or      A + 40 = 300

A = 20             or      A = 260

Answer 2

Step-by-step explanation:

Sin 30=sin(90-60)

Then cos(40+A)=(cos 60)

A=20 ans