Question

Hei, cine ma poate ajuta la acest exercițiu la mate? Va rog frumos, chiar nimeni nu ma poate ajuta? nu cer atat de mult, macar primele 3-4 sa am un exemplu ceva...​

Answer 1

Răspuns:

a,x²-4(x+1)=2-3x

x²-4x-4-2+3x=0

x²-x-6=0

x²-4-x-2=0

(x-2)(x+2)-(x+2)=0

(x+2)(x-2-1)=0

(x+2)(x-3)=0

x+2=0

x1= -2

x-30

x=3

x={-2,3}

______________

c)(x+2)(1-x)=-10

-x²-2x+x+2+10=0

-x²-x+12=0

-x²-x+9+3=0

(9-x²)+(3-x)=0

(3-x)(3+x)+(3-x)=0

(3-x)(3+x+1)=0

(3-x)(4+x)=0

3-x=0

x=3

4+x=0

x= -4

x={ -4,3}

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e)(x-2)(x+1)=3(x+1)

(x-2)(x+1)-3(x+1)=0

(x+1)(x-2-3)=0

(x+1)(x-5)=0

x+1=0

x= -1

x-5=0

x=5

x={-1,5}

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g)(2x-1)(2x+1)-(x+4)²= -22

4x²-1-(x²+8x+16)=-22

4x²-1-x²-8x-16+22=0

3x²-8x+5=0

3x²-3x-5x+5=0

3x(x-1)-5(x-1)=0

(x-1)(3x-5)=0]

x-1==0   x=1

3x-5=0   x=5/3∉Z

x=1

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b)x²+2(x-4)=3x-8

x²+2x-8=3x-8

x²+2x=3x

x²+2x-3x=0

x²-x=0

x(x-1)=0

x1=0

x2=1

Explicație pas cu pas: