Question

Preciso calcular cos 45

Answer 1

Oi Fatima

cos(45) = cos(90/2) 

formula

cos(x/2)  = √[(1 + cos(x))/2]

cos(45)  = √[(1 + cos(90))/2]

cos(45) = √[(1 + 0)/2] = 1/√2 = √2/2 

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