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Ex 3.3
Last updated at Dec. 13, 2024 by Teachoo
Ex 3.3, 18 Prove that 〖sin x − 〗siny /(𝑐𝑜𝑠x + 𝑐𝑜𝑠y ) = tan (x − y)/2 Solving L.H.S 〖sin x − 〗siny /(𝑐𝑜𝑠x + 𝑐𝑜𝑠y ) = 〖𝟐 𝒄𝒐𝒔((𝒙 + 𝒚 )/𝟐)〗〖 𝒔𝒊𝒏((𝒙 − 𝒚 )/𝟐) 〗/(𝟐 𝒄𝒐𝒔((𝒙 + 𝒚 )/𝟐) 𝒄𝒐𝒔((𝒙 − 𝒚 )/𝟐) ) = 𝑠𝑖𝑛" " ((𝑥 − 𝑦 )/2)/(𝑐𝑜𝑠((𝑥 − 𝑦 )/2) ) = tan (𝒙 − 𝒚 )/𝟐 = R.H.S Hence L.H.S. = R.H.S. Hence proved