hasil operasi berikut.
a. A+B
b. B-A
c. 3A-B
d. 5A- 3B + 2A
3. Tentukan hasil operasi aljabar berikut.
a. (3m – 4n+ 1)(m +2)
b. (6p + 1)(p – 4) + 2p(7 – p)
4. Jika diketahui P = x – 5 dan Q = 2x + 3, tentukan
hasil operasi berikut.
a. Q-2P2
b. 3(P+Q)
2. Diketahui A = 2x + 3y dan B = 6x – y. Tentukan
Jawaban:
2. A= 2x + 3y
B = 6x – y.
a. A+B=2x + 3y +6x – y
= 2x+6x + 3y – y
= 8x+ 2y
b. B-A=6x – y – (2x + 3y )
= 6x – y – 2x – 3y
= 6x – 2x – y- 3y
= 4x – 4y
c. 3A-B= 3(2x + 3y )-(2x + 3y )
= 6x+9y-2x-3y
= 6x-2x+9y-3y
= 4x + 6y
d. 5A- 3B + 2A
= 5(2x+3y )-3(6x-y)+2(2x + 3y)
=10x+15y-18x+3y+4x+6y
= 10x-18x+4x+15y+3y+6y
= -4x+24y
3.
a. (3m – 4n+ 1)(m +2)
=3m²-4mn+m+6m-8n+2
=3m²-4mn+7m-8n+2
b. (6p + 1)(p – 4) + 2p(7 – p)
=6p²-24p+p-4+14p-2p²
= 4p²-9p+1
4. P = x – 5
Q = 2x + 3,
a. Q-2P2
= (2x + 3)-2(x – 5)²
= 2x + 3 – 2(x²+5x+25)
= 2x + 3 – 2x²-10x+50
= – 2x²-8x+52
b. 3(P+Q)
=3(x – 5 + 2x + 3)
= 3(3x – 2)
= 9x-6