Question

Tolong dong 3 nomer ini plisss butuh bgt besok dikumpulin:( makasih

Answer 1

No 46)

Berarti :

(A (x-2) + B(3x+1))/(3x+1) (x-2) = (5x-3)/(3x+1) (x-2)

AX - 2A + (3BX + B) = 5x - 3

(A+3B)X - 2A + B = 5x - 3

A+ 3B = 5 --> -2A -6B = -10

-2A + B = -3--> -2A + B = -3

------------------------------------- -

-7B = -7

B = 1

A + 3B = 5

A + 3 = 5

A = 2

4A + B = 4(2)+1) = 9

No 47)

x² + y² = 5

(x+y)² -2xy = 5

(2)² -2xy = 5

4 - 2xy = 5

-2xy = 1

xy = -1/2

Jadi :

x³ + y³ = (x+y)³ -3xy (x+y) = (2)³ -3(-1/2) (2) = 8 + (3/2) (2) = 8+3 = 11