$$(cosA+sinA)^{2} +(cosA-sinA)^{2}$$ Â is equals to
Expression : $$(cosA+sinA)^{2} +(cosA-sinA)^{2}$$
= $$(cos^2 A + sin^2 A + 2.sin A.cos A) + (cos^2 A + sin^2 A - 2.sin A.cos A)$$
= $$(1 + 2.sin A.cos A) + (1 - 2.sin A.cos A)$$
= $$1 + 1 = 2$$
=> Ans - (C)
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