Question

evaluate 2sinA + 4 cos A - 5 cosecA + 2cotA if tan39/cot51+sin39/cos51=cosecA ​

Answer 1

Answer:

-2.07179677

Step-by-step explanation:

tan 39/cot 51+sin 39/cos 51=cosec A

tan 39/cot (90-39)+sin 39/cos(90-39)=cosec A

tan 39/tan 39+sin 39/sin39=cosec A

(cot (90-A)=tan A, cos(90-A)=sinA)

1+1=cosec A

2=cosec A

cosec A=cosec 30°

A=30°

2SinA+4CosA-5CosecA+2CotA

2Sin30+4Cos30-5Cosec30+2Cot30

2*0.5 + 4*0.866025403 - 5*2 + 2*1.732050808

1 + 3.464101615 - 10 + 3.464101615

1 + 6.92820323 - 10

7.92820323 - 10

-2.07179677(This is Answer)

Answer 2

Answer:

cot51=90-39 = tan39

cos51=90-39 = sin39