Mohon bantu caranya​

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Mohon bantu caranya​

Mohon bantu caranya​

Penjelasan dengan langkah-langkah:

3x²+4x-2= 0

a = 3, b= 4, c = -2

x1 + x2 = -b/a = -4/3

x1 . x2 = c/a = -2/3

nilai 4/x1 + 4/x2

= 4.x2/x1.x2 + 4.x1/x1.x2

= 4(x1+x2)/x1.x2

= 4.(-4/3)/ (-2/3)

= (-16/3) / (-2/3)

= 8

Jawab:

Penjelasan dengan langkah-langkah:

persamaan kuadrat.

ax² + bx + c = 0

x₁ + x₂ = -b/a

x₁ . x₂ = c/a

11.

3x² + 4x – 2 = 0

x₁ + x₂ = -4/3

x₁ . x₂ = -2/3

4/x₁ + 4/x₂ = (4x₂ + 4x₁)/x₁.x₂

.                  = 4 ( x₁ + x₂ )/( x₁ . x₂ )

.                  = 4 ( -4/3 ) / ( -2/3 )

.                  = -16/3  x  -3/2

.                  = 8

opsi pilihan  ( B )

12.

pk lama .

3x² + x – 1 = 0

x₁ + x₂ = -1/3

x₁ . x₂ = -1/3

Pk baru .

A = x₁ + 1

B = x₂ + 1

A + B = x₁ + 1 + x₂ + 1

.         = x₁ + x₂ + 2

.         = -1/3 + 2

.         = 5/3

A . B = ( x₁ + 1 ) ( x₂ + 1 )

.        = x₁ . x₂ + x₁ + x₂ + 1

.        = -1/3 – 1/3 + 1

.       = -2/3 + 1

.       = 1/3

PK baru menjadi ;

x² – ( A + B ) x + ( A . B ) = 0

x² – ( 5/3 ) x + ( 1/3 ) = 0

x² – 5/3  x + 1/3 = 0

3x² – 5x + 1 = 0

atau pakai rumus invers.

invers dari ( x + 1 ) ————> ( x – 1 )

lalu subtitusi ( x – 1 ) ke pk lama;

3 ( x – 1 )² + ( x – 1 ) – 1 = 0

3 ( x² – 2x + 1 ) + x – 1 – 1 = 0

3x² – 6x + 3 + x – 2 = 0

3x² – 5x + 1 = 0

hasilnya sama

opsi pilihan  ( C )

semoga bisa membantu