Respostas

  • Usuário do Brainly
2014-07-23T19:38:45-03:00
A)
y² -121=0
y²=121
y=√121
y'=11
y"=-11
S={-11,11}

b)
2y²-98=0
2y²=98
y²=98÷2
y²=49
y=√49
y'=7
y"=-7
S={-7,7}

c)
2y²=-4
y²=-4÷2
y²=-2
y=√-2  ∉ R
S={  }

d)
4y²+100=0
4y²=-100
y²=-100÷4
y²=-25
y=√-25  ∉ R
S={  }
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