Respostas

2013-10-22T00:36:48-02:00
Seja x/2=a >>> (sen a + cos a)²= sen²a + 2sena.cosa + cos²a , mas sen²a + cos²a =1 
(sen a + cos a)²=1+2.sena.cosa , sen(a+a)= sena.cosa + sena.cos=
2sena.cosa=sen2a
(sena+coasa)²=1+2sena.cosa=1+sen2a=1+sen2.x/2=1+senx.
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