Question

Evaluate: (secA+tanA)(1-sinA)​

Answer 1

Answer:

Step-by-step explanation:

(sec A+tan A)(1-sin A)=sec A+tan A-sec A×sin A-tan A×sin A

                                  =(1/cos A)+tan A-(1/cos A)(sin A)-(sin²A/cos A)

                                  =[(1-sin²A)/cos A]+tan A-tan A

                                  =cos²A/cos A

                                  =cos A

Answer 2

Answer:

Cos A

Step-by-step explanation:

= ( Sec A + Tan A ) ( 1 - Sin A)

= ( 1 / cos A + Sin A / cos A) ( 1 - Sin A)

[ formula , sec A =1/ cos A and Tan A = sin A / cos A ]

= ( 1 + sin A ) ( 1 - Sin A )

cos A

= ( 1 + sin A ) ( 1 - Sin A )

cos A

[formula, (A + B ) ( A- B) = A square - B square ]

= 1 square - sin A square

Cos A

= 1 - sin A square

Cos A

[ formula, 1 - sin A square = cos A square ]

= cos A square

Cos A

= Cos A.