Prove that: sin 23^0+sin 37^0=cos7^0...

Prove that: `sin 23^0+sin 37^0=cos7^0`

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To proof: `sin(23^o)+sin(37^o)=cos(7^o)`
Let,
L.H.S=`sin(23^o)+sin(37^o)`
As we know the formula,
`sinA+sinB=2sin((A+B)/2)cos((A-B)/2)`
So, L.H.S`=2sin(((23^o)+(37^o))/2).cos(((23^o)-(37^o))/2)`
L.H.S=` 2sin(30^o)cos(7^o)`
L.H.S=`(2*1/2)cos(7^o)`
...

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