Matemática
judan
13

1)Resolva, em |R, as equações do 2° grau abaixo:   a)x²-3x-10 = 0 b) 6x²-x-1 = 0 c)2x²-6x-140 = 0 d)x²+9x+8 = 0 e)x²-6x+8 = 0 f)3x²-x-2= 0 g) x²-x+6= 0 h)(x+3).(x+2)-2x=16  

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REJAPSI

a)x²-3x-10 = 0 D=(-3²)-4.1.(-10) D=9+40 D=49 x'=3+7/2.1 x'=10/2 x'=5 x"=3-7/2.1 x"=-4/2 x"=-2 b) 6x²-x-1 = 0 D=(-1²)-4.6.(-1) D=1+24 D=25 x'=1+5/2.6 x'=6/12 x'=3/6 x"=1-5/2.6 x"=-4/12 x"=-2/6 c)2x²-6x-140 = 0 D=(-6²)-4.2.(-140) D=36+1120 D=1156 x'=6+34/2.2 x'=40/4 x'=4 x"=6-34/2.2 x"=-28/4 x"=-7 d)x²+9x+8 = 0 D=9²-4.1.8 D=81-32 D=49 x'=-9+7/2.1 x'=-2/2 x'=-1 x"=-9-7/2.1 x"=-16/2 x"=-8 e)x²-6x+8 = 0 D=(-6²)-4.1.8 D=36-32 D=4 x'=6+2/2.1 x'=8/2 x'=4 x"=6-2/2.1 x"=4/2 x"=2 f)3x²-x-2= 0 D=(-1²)-4.3.(-2) D=1+24 D=25 x'=1+5/2.3 x'=6/6 x'=1 x"=1-5/2.3 x"=-4/6 x"=-2/3 g) x²-x+6= 0 D=(-1²)-4.1.6 D=1-24 D=-23 Não temos raizes reais porque o delta é negativo h)(x+3).(x+2)-2x=16 x²+2x+3x+6-2x=16 x²+3x-10=0 D=3²-4.1.(-10) D=9+40 D=49 x'=-3+7/2.1 x'=4/2 x'=2 x"=-3-7/2.1 x"=-10/2 x"=-5

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