Cos x + cos y formula
Ex 3.3, 11 Important
Misc 3
Misc 4 Important
Ex 3.3, 14
Ex 3.3, 15
Misc 5
Misc 7 Important
Example 16 Important
Ex 3.3, 16 Important
Ex 3.3, 17
Ex 3.3, 18 Important You are here
Ex 3.3, 19
Ex 3.3, 20
Ex 3.3, 21 Important
Example 17 Important
Misc 6 Important
cos x + cos y formula
Last updated at April 16, 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