Resposta:
Explicação passo a passo:
2)
a)
[tex]5x^{2} =0\\x^{2} =0/5\\x^{2} =0\\x=\sqrt{0} \\x=0[/tex]
b)
[tex]3x^{2} =0\\x^{2} =0/3\\x^{2} =0\\x=\sqrt{0} \\x=0[/tex]
c)
[tex]4x^{2} =0\\x^{2} =0/4\\x^{2} =0\\x=\sqrt{0} \\x=0[/tex]
d)
[tex]7x^{2} =0\\x^{2} =0/7\\x^{2} =0\\x=\sqrt{0} \\x=0[/tex]
e)
[tex]10x^{2} =0\\x^{2} =0/10\\x^{2} =0\\x=\sqrt{0} \\x=0[/tex]
f)
[tex]x^{2} -5x=0\\x.(x-5)=0\\x=0\\\ou\\\\x-5=0\\x=5[/tex]
g)
[tex]x^{2} -7x=0\\x.(x-7)=0\\x=0\\ou\\x-7=0\\x=7[/tex]
h)
[tex]x^{2} +3x=0\\x.(x+3)=0\\x=0\\ou\\x+3=0\\x=-3[/tex]
i)
[tex]5x^{2} +10x=0\\x.(5x+10)=0\\x=0\\ou\\5x+10=0\\5x=-10\\x=-10/5\\x=-2[/tex]
j)
[tex]3x^{2} -6x=0\\x.(3x-6)=0\\x=0\\ou\\3x-6=0\\3x=6\\x=6/3\\x=2[/tex]
3)
a)
[tex]6x^{2} =0\\x^{2} =0/6\\x^{2} =0\\x=\sqrt{0} \\x=0[/tex]
b)
[tex]x^{2} -49=0\\x^{2} =49\\x=\sqrt{49} \\x=+7\\ou\\x=-7[/tex]
c)
[tex]x^{2} -9=0\\x^{2} =9\\x=\sqrt{9} \\x=+3\\ou\\x=-3[/tex]
d)
[tex]2x^{2} -32=0\\2x^{2} =32\\x^{2} =32/2\\x^{2} =16\\x=\sqrt{16} \\x=+4\\ou\\x=-4[/tex]
e)
[tex]x^{2} +25=0\\x^{2} =-25\\x=\sqrt{-25} \\[/tex]
S =∅
f)
[tex]-5x^{2} -20=0\\-5x^{2} =20\\5x^{2} =-20\\\\x^{2} =-20/5\\x^{2} =-4\\x=\sqrt{-4} \\[/tex]
S=∅
g)
[tex]8x^{2} -8=0\\8x^{2} =8\\x^{2} =8/8\\x^{2} =1\\x=\sqrt{1} \\x=+1\\ou\\x=-1[/tex]
