sin A + cos A/ sinA- cos A + sin A - cos / sin A+ cos A =2 / sin A square A - cos A square= 2/2 sin square A -1= 2/1-2cos A square
Answers
LHS =
( sinA+cosA). ( sinA - cosA)
----------------------- + ----------------------
( sinA - cosA) ( sinA+ cosA)
( sinA+ cosA)²+ ( sinA - cosA)²
= ------------------------------------------------
( sin²A - cos²A)
2( sin²A + cos²A)
= ------------------------------------
( sin²A - cos²A)
2
= --------------------------- = middle term (1)
( sin²A - cos²A)
2
= ------------------------------
[ sin²A-(1- sin²A) ]
2
= ------------------. = middle term (2)
2sin²A-1
2
= -----------------------------
[ 2(1- cos²A) -1]
2
=. ----------------------
1 - 2 cos²A
= RHS
Hence proved