Question

If tan 21° 48 = •4. Then 5 sin Φ +2 cos Φ = 5 solved it

Answer 1

Hay sir, Always good questions

According to the question we know that

tan21°48 = 4 = 2/5

so, sin 21° 48 = 2/√29

cos 21°48 = 5/√29

5 sin Φ +2 cos Φ = 5

If we can divide both sides by √29 then,

5/29 sinΦ + 2/29 cosΦ = 5/29

=> cos21°48 sinΦ + sin21°48 cosΦ = cos21°48

=> sin(Φ+21°48) = cos21°48 = sin 68°12

=> Φ +21°48 = n. 180°+ (-1)^n 68°12

=> Φ = n^180°-21°48 + (-1)^n 68°12



I hope it's help you

Regards : Sangela