উৎপাদকে বিশ্লেষণ কর: (১-৩০)
১. ab(x – y) – bc(x – y)
সমাধান: ab(x – y) – bc(x – y)
= (x – y)(ab – bc)
= (x – y){b(a – c)}
= b(x – y)(a – c)
২. 9x2 + 24x + 16
সমাধান: 9x2 + 24x + 16
= (3x)2 + 2.3x.4 + (4)2
= (3x + 4)2
৩. a4 – 27a2 + 1
সমাধান: a4 – 27a2 + 1
= (a2)2 – 2.a2.1 + 12– 25a2
= (a2 – 1)2 – (5a)2
= (a2 – 1 + 5a)(a2 -1 -5a)
৪. x4 – 6x2y2 + y4
সমাধান: x4 – 6x2y2 + y4
= (x2)2 – 2.x2.y2 + (y2)2 – 4x2y2
= (x2 – y2)2 – (2xy)2
= (x2 – y2 – 2xy)(x2 – y2 + 2xy)
৫. (a2-b2)(x2-y2)+4abxy
সমাধান: (a2 – b2)(x2 – y2) + 4abxy
= a2x2 – b2x2– a2y2 + b2y2 + 4abxy
= (ax)2 + (by)2 + 2abxy – (bx)2 – (ay)2 + 2axby
= (ax)2 + (by)2 + 2abxy – {(bx)2 + (ay)2 – 2axby}
= (ax + by)2 – (bx – ay)2
= (ax + by + bx – ay)(ax + by – bx + ay)
৬. 4a2-12ab+9b2-4c2
সমাধান: 4a2 – 12ab + 9b2 – 4c2
= (2a)2 – 2.2a.3b + (3b)2 – (2c)2
= (2a – 3b)2 – (2c)2
= (2a – 3b – 2c)(2a – 3b + 2c)
৭. a2 + 6a + 8 – y2 + 2y
সমাধান: a2 + 6a + 8 – y2 + 2y
= a2 + 2.a.3 + 32 – 12 + 2.1.y – y2
= (a + 3)2– (12 – 2.1.y + y2)
= (a + 3)2– (1 – y)2
= (a + 3 – 1 + y)(a + 3 + 1 – y)
= (a + y + 2)(a – y + 4)
৮. 16x2 – 25y2 – 8xz + 10yz
সমাধান: 16x2 – 25y2 – 8xz + 10yz
= (4x)2 – (5y)2 – 2z(4x – 5y)
= (4x – 5y)(4x + 5y) – 2z(4x – 5y)
= (4x – 5y)(4x + 5y – 2z)
৯. 2b2c2 + 2c2a2 + 2a2b2 – a4 – b4 – c4
সমাধান: 2b2c2 + 2c2a2 + 2a2b2 – a4 – b4 – c4
= 4a2b2 – a4 – b4 – c4 – 2a2b2 + 2b2c2 + 2c2a2
= (2ab)2 – {(a2)2 + (b2)2 + (c2)2 + 2a2b2 + 2b2 (-c)2 + 2(-c)2a2}
= (2ab)2 – (a2 + b2 – c2)2
= (2ab – a2 – b2 + c2)(2ab + a2 + b2 – c2)
= {c2 – (a2 + b2 – 2ab)}{(a + b)2 – c2}
= {c2 – (a – b)2}{a + b – c)(a + b + c)
= (c – a + b)(c + a – b)(a + b – c)(a + b + c)
১০. x2 + 13x + 36
সমাধান: x2 + 13x + 36
= x2 + 9x + 4x + 36
= x(x + 9) + 4(x + 9)
= (x + 9)(x+ 4)
১১. x4 + x2 – 20
সমাধান: x4 + x2 – 20
= x4 + 5x2 – 4x2 – 20
= x2(x2 + 5) – 4(x2 + 5)
= (x2 – 4)(x2 + 5)
= (x2 – 22)(x2 + 5)
= (x – 2)(x + 2)(x2 + 5)
১২. a2 – 30a + 216
সমাধান: a2 – 30a + 216
= a2 – 18a – 12a + 216
= a(a – 18) – 12(a – 18)
= (a – 12)(a – 18)
১৩. a8 – a4 – 2
সমাধান: a8 – a4 – 2
= a8 – 2a4 + a4 – 2
= a4(a4 – 2) + 1(a4 – 2)
= (a4 + 1)(a4 – 2)
১৪. x2 – 37x – 650
সমাধান: x2 – 37x – 650
= x2 + 13x – 50x – 650
= x(x + 13) – 50(x – 13)
= (x – 50)(x + 13)
১৫. 9x2y2 – 5xy2 – 14y2
সমাধান: 9x2y2 – 5xy2 – 14y2
= y2(9x2 – 5x – 14)
= y2(9x2 – 14x + 9x – 14)
= y2{x(9x -14) + 1(9x – 14)}
= y2(x + 1)(9x – 14)
১৬. 4x4 – 27x2 – 81
সমাধান: 4x4 – 27x2 – 81
= 4x4– 36x2 + 9x2-81
= 4x2(x2 – 9) + 9(x2 – 9)
= (4x2 + 9)(x2 – 9)
= (4x2 + 9)(x2 – 32)
= (4x2 + 9)(x – 3)(x + 3)
১৭. ax2 + (a2 + 1)x + a
সমাধান: ax2 + (a2 + 1)x + a
= ax2 + a2x + x + a
= ax(x + a) + 1(x + a)
= (ax + 1)(x + a)
১৮. 3(a2 + 2a)2 – 22(a2 + 2a) + 40
সমাধান: 3(a2 + 2a)2 – 22(a2 + 2a) + 40
মনে করি, a2 + 2a = x
∴ প্রদত্ত রাশি = 3x2 – 22x + 40
= 3x2– 12x – 10x + 40
= 3x(x -4) – 10(x – 4)
= (3x – 10)(x – 4)
= {3.(a2 + 2a) – 10}{a2 + 2a – 4} [মান বসিয়ে]
= (3a2 + 6a – 10)(a2 + 2a – 4)
১৯. 14(x + z)2 – 29(x + z)(x + 1) – 15(x + 1)2
সমাধান: 14(x + z)2 – 29(x + z)(x + 1) – 15(x + 1)2
মনে করি, x + z = a; x + 1 = b
∴ প্রদত্ত রাশি = 14a2 – 29ab – 15b2
= 14a2 – 35ab + 6ab – 15b2
= 7a(2a – 5b) + 3b(2a – 5b)
= (7a + 3b)(2a – 5b)
= {7(x + z) + 3(x + 1)}{2(x + z) – 5(x + 1)} [মান বসিয়ে]
= (7x + 7z + 3x + 3)(2x + 2z – 5x – 5)
= (10x + 7z + 3)(2z – 3x – 5)
২০. (a – 1)x2 + a2xy + (a + 1)y2
সমাধান: (a – 1)x2 + a2xy + (a + 1)y2
মনে করি, a – 1 = p এবং a + 1 = q
তাহলে, (a – 1)(a + 1) = pq
বা, a2 – 1 = pq
বা, a2= pq+1
∴ প্রদত্ত রাশি = px2 + (pq + 1)xy + qy2
= px2 + pqxy + xy + qy2
= px(x + qy) + y(x + qy)
= (px + y)(x + qy)
= {(a – 1)x + y}{x + (a + 1)y} [মান বসিয়ে]
= (ax – x + y)(x + ay + y)
২১. x3 + 3x2 + 3x + 2
সমাধান: x3 + 3x2 + 3x + 2
= x3 + 3.x2.1 + 3.x.12 + 13 + 1
= (x + 1)3 + 13
= {(x + 1) + 1}{(x + 1)2 – (x + 1).1 + 12}
= (x + 2)(x2 + 2x + 1 – x – 1 + 1)
= (x + 2)(x2 + x + 1)
২২. a3 – 6a2 + 12a – 9
সমাধান: a3 – 6a2 + 12a – 9
= a3 – 3.a2.2 + 3.a.(2)2 – 23 – 1
= (a – 2)3 – 13
= (a – 2 – 1){(a – 2)2 + (a – 2).1 + 12}
= (a – 3)(a2 – 2.a.2 + 22 + a – 2 + 1)
= (a – 3)(a2 – 4a + 8 + a – 2 + 1)
= (a – 3)((a2 – 3a + 3)
২৩. a3-9b3+(a+b)3
সমাধান: a3 – 9b3 + (a + b)3
= a3 – b3 + (a + b)3 – 8b3
= (a – b)(a2 + ab + b2) + (a + b)3 – (2b)3
= (a – b)(a2 + ab + b2) + (a + b – 2b){(a + b)2 + (a + b).2b + (2b)2}
= (a – b)(a2 + ab + b2) + (a – b)(a2 + b2 + 2ab + 2ab + 2b2 + 4b2)
= (a – b)(a2 + ab + b2) + (a – b)(a2 + 4ab + 7b2)
= (a – b)( a2 + ab + b2 + a2 + 4ab + 7b2)
= (a – b)(2a2 + 5ab + 8b2)
২৪. 8x3 + 12x2 + 6x – 63
সমাধান: 8x3 + 12x2 + 6x – 63
= (2x)3 + 3.(2x)2.1 + 3.2x.12 + 13 + 6x – 64
= (2x + 1)3 – 64
= (2x + 1)3 – 43
= (2x + 1 – 4){(2x + 1)2 + (2x + 1)4 + 42)
= (2x + 1)(4x2 + 4x + 1 + 8x + 4 + 16)
= (2x + 1)(4x2 + 12x + 21)
২৫. 8a3 + b3/27
সমাধান: 8a3 + b3/27
= (2a)3 + (b/3)3
= (2a + b/3) + {(2a)2 – 2a.b/3 + (b/3)2}
= (2a + b/3)(4a2 – 2ab/3 + b2/9)
= {(6a + b)/3}{36a2 – 6ab + b2)/9}
= (6a + b)(36a2 – 6ab + b2)/27
২৬. a6/27-b6
সমাধান: a6/27 – b6
= (a2/3)3 – (b2)3
= (a2/3 – b2){(a2/3)2 + (a2/3).b2 + (b2)2}
= (a2/3 – b2)(a4/9 + a2b2/3 + b4)
২৭. 4a2 + 1/4a2 – 2 + 4a – 1/a
সমাধান: 4a2 + 1/4a2 – 2 + 4a – 1/a
= (2a)2 + (1/2a)2 – 2.2a.(1/2a) + 2(2a – 1/2a)
= (2a – 1/2a)2 + 2(2a – 1/2a)
= (2a – 1/2a)2(2a – 1/2a + 2)
২৮. (3a + 1)3 – (2a – 3)3
সমাধান: (3a + 1)3 – (2a – 3)3
= {(3a + 1) – (2a – 3)}{(3a + 1)2 + (3a + 1)(2a – 3) + (2a – 3)2}
= (3a + 1 – 2a + 3){(3a)2 + 2.3a.1 + 12 + 3a.2a + 2a – 3a.3 – 3 + (2a)2 – 2.2a.3 + 32}
= (a + 4)(9a2 + 6a + 1 + 6a2 + 2a – 9a – 3 + 4a2 – 12a + 9)
= (a + 4)(19a2 – 13a + 7)
২৯. (x + 2)(x + 3)(x + 4)(x + 5) – 48
সমাধান: (x + 2)(x + 3)(x + 4)(x + 5) – 48
= (x + 2)(x + 5)(x + 3)(x + 4) – 48
= (x2 + 2x + 5x + 10)(x2 + 3x + 4x + 12) – 48
= (x2 + 7x + 10)(x2 + 7x + 12) – 48
মনে করি, x2 + 7x + 10 = m
∴প্রদত্ত রাশি = m(m + 2) – 48
= m2 + 2m – 48
= m2 + 8m – 69m – 48
= m(m + 8) – 6(m + 8)
= (m – 6)(m + 8)
= (x2 + 7x + 10 – 6)(x2 + 7x + 10 + 8) [মান বসিয়ে]
= (x2 + 7x + 4)(x2 + 7x + 18)
৩০. (x – 1)(x – 3)(x – 5)(x – 7) – 65
সমাধান:(x – 1)(x – 3)(x – 5)(x – 7) -65
= (x – 1)(x – 7)(x – 3)(x – 5) – 65
= (x2 – 7x – x + 7)(x2 – 5x – 3x + 15) – 65
= (x2 – 8x + 7)(x2 – 8x + 15) – 65
ধরি, x2 – 8x + 7 = p
∴প্রদত্ত রাশি = p(p + 8) – 65
= p2 + 8p – 65
= p2 + 13p – 5p – 65
= p(p + 13) – 5(p + 13)
= (p – 5)(p + 13)
= (x2 – 8x + 7 -5)(x2 – 8x + 7 + 13) [মান বসিয়ে]
= (x2 – 8x + 2)(x2 – 8x + 20)
৩১. দেখাও যে, (x + 1)(x + 2)(3x – 1)(3x – 4) = (3x2 + 2x – 1)(3x2 + 2x – 8)
সমাধান:
বামপক্ষ
= (x + 1)(x + 2)(3x – 1)(3x – 4)
= (x + 1)(3x – 1)(x + 2)(3x – 4)
= (3x2 + 3x – x – 1)(3x2+ 6x – 4x – 8)
= (3x2 + 2x – 1)(3x2 + 2x – 8)
= ডানপক্ষ (দেখানো হলো)