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Page 2 d 2x(1 - 4x)(1 + 4x) S o l u t i o n : d 2x(1 - 4x)(1 + 4x) (2x-32x3)=2x(1-16x2)=2x(1-4x)(1+4x) Q u e s t i o n : 1 2 0 Tick ? the correct answer: x 3 - 144x = ? a x(x - 12) 2 b x(x + 12) 2 c x(x - 12)(x + 12) d none of these S o l u t i o n : c x(x - 12)(x + 12) x3 - 144x=x(x2 -144)=x(x-12)(x+12) Q u e s t i o n : 1 2 1 Tick ? the correct answer: (2 - 50x 2 ) = ? a 2(1 - 5x) 2 b 2(1 + 5x) 2 c (2 - 5x)(2 + 5x) d 2(1 - 5x)(1 + 5x) S o l u t i o n : d 2(1 - 5x)(1 + 5x) 2-50x2 =2(1-25x2)=2(1-5x)(1+5x) Q u e s t i o n : 1 2 2 Tick ? the correct answer: a 2 + bc + ab + ac = ? a (a + b)(a + c) b (a + b)(b + c) c (b + c)(c + a) d a(a + b + c) S o l u t i o n : a (a + b)(a + c) a2+bc +ab +ac=a2+ab+bc +ac=a(a+b)+c(a+b)=(a+c)(a+b) Q u e s t i o n : 1 2 3 Tick ? the correct answer: pq 2 + q(p - 1) - 1 = ? a (pq + 1)(q - 1) b p(q + 1)(q - 1) c q(p - 1)(q + 1) d (pq - 1) (q + 1) S o l u t i o n : d (pq - 1) (q + 1) pq2+q(p-1)-1=pq2+qp-q-1=pq(q+1)-1(q+1)=(pq-1)(q+1) Q u e s t i o n : 1 2 4 Tick ? the correct answer: ab - mn + an - bm = ? a (a - b)(m - n) b (a - m)(b + n) c (a - n)(m + b) d (m - a)(n - b) S o l u t i o n : b (a - m)(b + n) ab-mn+an-bm=ab+an-mn-bm=a(b+n)-m(n+b)=(a-m)(b+n) Q u e s t i o n : 1 2 5 Tick ? the correct answer: ab - a - b + 1 = ? a (a - 1)(b - 1) b (1 - a)(1 - b) c (a - 1)(1 - b) d (1 - a)(b - 1) S o l u t i o n : a (a - 1)(b - 1) ab-a-b+1=a(b-1)-1(b-1)=(a-1)(b-1) Q u e s t i o n : 1 2 6 Tick ? the correct answer: x 2 - xz + xy - yz = ? a (x - y)(x + z) b (x - y)(x - z) c (x + y)(x - z) Page 3 d 2x(1 - 4x)(1 + 4x) S o l u t i o n : d 2x(1 - 4x)(1 + 4x) (2x-32x3)=2x(1-16x2)=2x(1-4x)(1+4x) Q u e s t i o n : 1 2 0 Tick ? the correct answer: x 3 - 144x = ? a x(x - 12) 2 b x(x + 12) 2 c x(x - 12)(x + 12) d none of these S o l u t i o n : c x(x - 12)(x + 12) x3 - 144x=x(x2 -144)=x(x-12)(x+12) Q u e s t i o n : 1 2 1 Tick ? the correct answer: (2 - 50x 2 ) = ? a 2(1 - 5x) 2 b 2(1 + 5x) 2 c (2 - 5x)(2 + 5x) d 2(1 - 5x)(1 + 5x) S o l u t i o n : d 2(1 - 5x)(1 + 5x) 2-50x2 =2(1-25x2)=2(1-5x)(1+5x) Q u e s t i o n : 1 2 2 Tick ? the correct answer: a 2 + bc + ab + ac = ? a (a + b)(a + c) b (a + b)(b + c) c (b + c)(c + a) d a(a + b + c) S o l u t i o n : a (a + b)(a + c) a2+bc +ab +ac=a2+ab+bc +ac=a(a+b)+c(a+b)=(a+c)(a+b) Q u e s t i o n : 1 2 3 Tick ? the correct answer: pq 2 + q(p - 1) - 1 = ? a (pq + 1)(q - 1) b p(q + 1)(q - 1) c q(p - 1)(q + 1) d (pq - 1) (q + 1) S o l u t i o n : d (pq - 1) (q + 1) pq2+q(p-1)-1=pq2+qp-q-1=pq(q+1)-1(q+1)=(pq-1)(q+1) Q u e s t i o n : 1 2 4 Tick ? the correct answer: ab - mn + an - bm = ? a (a - b)(m - n) b (a - m)(b + n) c (a - n)(m + b) d (m - a)(n - b) S o l u t i o n : b (a - m)(b + n) ab-mn+an-bm=ab+an-mn-bm=a(b+n)-m(n+b)=(a-m)(b+n) Q u e s t i o n : 1 2 5 Tick ? the correct answer: ab - a - b + 1 = ? a (a - 1)(b - 1) b (1 - a)(1 - b) c (a - 1)(1 - b) d (1 - a)(b - 1) S o l u t i o n : a (a - 1)(b - 1) ab-a-b+1=a(b-1)-1(b-1)=(a-1)(b-1) Q u e s t i o n : 1 2 6 Tick ? the correct answer: x 2 - xz + xy - yz = ? a (x - y)(x + z) b (x - y)(x - z) c (x + y)(x - z) d (x - y)(z - x) S o l u t i o n : c (x + y)(x - z) x2-xz+xy-yz=x(x-z)+y(x-z)=(x+y) (x-z) Q u e s t i o n : 1 2 7 Tick ? the correct answer: (12m 2 - 27) = ? a (2m - 3)(3m - 9) b 3(2m - 9)(3m - 1) c 3(2m - 3)(2m + 3) d none of these S o l u t i o n : c 3(2m - 3)(2m + 3) 12m2-27=3(4m2-9)=3 (2m-3)(2m+3) Q u e s t i o n : 1 2 8 Tick ? the correct answer: x 3 - x = ? a x(x 2 - x) b x(x - x 2 ) c x(1 + x)(1 - x) d x(x + 1)(x - 1) S o l u t i o n : d x(x + 1)(x - 1) x3-x=x( x2-1)=x(x-1)(x+1) Q u e s t i o n : 1 2 9 Tick ? the correct answer: 1 - 2ab - (a 2 + b 2 ) = ? a (1 + a - b)(1 + a + b) b (1 + a + b)(1 - a + b) c (1 + a + b)(1 - a - b) d (1 + a - b)(1 - a + b) S o l u t i o n : c (1 + a + b)(1 - a - b) 1-2ab-(a2 +b2)=1-2ab -a2-b2=1-(2ab +a2+b2)=1-(a+b)2=(1-a-b)(1+a+b) Q u e s t i o n : 1 3 0 Tick ? the correct answer: x 2 + 6x + 8 = ? a (x + 3)(x + 5) b (x + 3)(x + 4) c (x + 2)(x + 4) d (x + 1)(x + 8) S o l u t i o n : c (x + 2)(x + 4) x2+6x+8=x2+4x+2x+8=x(x+4)+2(x+4)=(x+2)(x+4) Q u e s t i o n : 1 3 1 Tick ? the correct answer: x 2 + 4x - 21 = ? a (x - 7)(x + 3) b (x + 7)(x - 3) c (x - 7)(x - 3) d (x + 7)(x + 3) S o l u t i o n : b (x + 7)(x - 3) x2+4x-21=x2+7x-3x-21=x(x+7)-3(x+7)=(x-3)(x+7) Q u e s t i o n : 1 3 2 Tick ? the correct answer: y 2 + 2y - 3 = ? a (y - 1)(y + 3) b (y + 1)(y - 3) c (y - 1)(y - 3) d (y + 2)(y - 3) S o l u t i o n : a (y - 1)(y + 3) y2+2y-3=y2+3y-y-3=y(y+3)-1(y+3)=(y-1)(y+3) Q u e s t i o n : 1 3 3 Tick ? the correct answer: 40 + 3x - x 2 = ? a (x + 5)(x - 8) b (5 - x)(8 + x) c (5 + x)(8 - x) Page 4 d 2x(1 - 4x)(1 + 4x) S o l u t i o n : d 2x(1 - 4x)(1 + 4x) (2x-32x3)=2x(1-16x2)=2x(1-4x)(1+4x) Q u e s t i o n : 1 2 0 Tick ? the correct answer: x 3 - 144x = ? a x(x - 12) 2 b x(x + 12) 2 c x(x - 12)(x + 12) d none of these S o l u t i o n : c x(x - 12)(x + 12) x3 - 144x=x(x2 -144)=x(x-12)(x+12) Q u e s t i o n : 1 2 1 Tick ? the correct answer: (2 - 50x 2 ) = ? a 2(1 - 5x) 2 b 2(1 + 5x) 2 c (2 - 5x)(2 + 5x) d 2(1 - 5x)(1 + 5x) S o l u t i o n : d 2(1 - 5x)(1 + 5x) 2-50x2 =2(1-25x2)=2(1-5x)(1+5x) Q u e s t i o n : 1 2 2 Tick ? the correct answer: a 2 + bc + ab + ac = ? a (a + b)(a + c) b (a + b)(b + c) c (b + c)(c + a) d a(a + b + c) S o l u t i o n : a (a + b)(a + c) a2+bc +ab +ac=a2+ab+bc +ac=a(a+b)+c(a+b)=(a+c)(a+b) Q u e s t i o n : 1 2 3 Tick ? the correct answer: pq 2 + q(p - 1) - 1 = ? a (pq + 1)(q - 1) b p(q + 1)(q - 1) c q(p - 1)(q + 1) d (pq - 1) (q + 1) S o l u t i o n : d (pq - 1) (q + 1) pq2+q(p-1)-1=pq2+qp-q-1=pq(q+1)-1(q+1)=(pq-1)(q+1) Q u e s t i o n : 1 2 4 Tick ? the correct answer: ab - mn + an - bm = ? a (a - b)(m - n) b (a - m)(b + n) c (a - n)(m + b) d (m - a)(n - b) S o l u t i o n : b (a - m)(b + n) ab-mn+an-bm=ab+an-mn-bm=a(b+n)-m(n+b)=(a-m)(b+n) Q u e s t i o n : 1 2 5 Tick ? the correct answer: ab - a - b + 1 = ? a (a - 1)(b - 1) b (1 - a)(1 - b) c (a - 1)(1 - b) d (1 - a)(b - 1) S o l u t i o n : a (a - 1)(b - 1) ab-a-b+1=a(b-1)-1(b-1)=(a-1)(b-1) Q u e s t i o n : 1 2 6 Tick ? the correct answer: x 2 - xz + xy - yz = ? a (x - y)(x + z) b (x - y)(x - z) c (x + y)(x - z) d (x - y)(z - x) S o l u t i o n : c (x + y)(x - z) x2-xz+xy-yz=x(x-z)+y(x-z)=(x+y) (x-z) Q u e s t i o n : 1 2 7 Tick ? the correct answer: (12m 2 - 27) = ? a (2m - 3)(3m - 9) b 3(2m - 9)(3m - 1) c 3(2m - 3)(2m + 3) d none of these S o l u t i o n : c 3(2m - 3)(2m + 3) 12m2-27=3(4m2-9)=3 (2m-3)(2m+3) Q u e s t i o n : 1 2 8 Tick ? the correct answer: x 3 - x = ? a x(x 2 - x) b x(x - x 2 ) c x(1 + x)(1 - x) d x(x + 1)(x - 1) S o l u t i o n : d x(x + 1)(x - 1) x3-x=x( x2-1)=x(x-1)(x+1) Q u e s t i o n : 1 2 9 Tick ? the correct answer: 1 - 2ab - (a 2 + b 2 ) = ? a (1 + a - b)(1 + a + b) b (1 + a + b)(1 - a + b) c (1 + a + b)(1 - a - b) d (1 + a - b)(1 - a + b) S o l u t i o n : c (1 + a + b)(1 - a - b) 1-2ab-(a2 +b2)=1-2ab -a2-b2=1-(2ab +a2+b2)=1-(a+b)2=(1-a-b)(1+a+b) Q u e s t i o n : 1 3 0 Tick ? the correct answer: x 2 + 6x + 8 = ? a (x + 3)(x + 5) b (x + 3)(x + 4) c (x + 2)(x + 4) d (x + 1)(x + 8) S o l u t i o n : c (x + 2)(x + 4) x2+6x+8=x2+4x+2x+8=x(x+4)+2(x+4)=(x+2)(x+4) Q u e s t i o n : 1 3 1 Tick ? the correct answer: x 2 + 4x - 21 = ? a (x - 7)(x + 3) b (x + 7)(x - 3) c (x - 7)(x - 3) d (x + 7)(x + 3) S o l u t i o n : b (x + 7)(x - 3) x2+4x-21=x2+7x-3x-21=x(x+7)-3(x+7)=(x-3)(x+7) Q u e s t i o n : 1 3 2 Tick ? the correct answer: y 2 + 2y - 3 = ? a (y - 1)(y + 3) b (y + 1)(y - 3) c (y - 1)(y - 3) d (y + 2)(y - 3) S o l u t i o n : a (y - 1)(y + 3) y2+2y-3=y2+3y-y-3=y(y+3)-1(y+3)=(y-1)(y+3) Q u e s t i o n : 1 3 3 Tick ? the correct answer: 40 + 3x - x 2 = ? a (x + 5)(x - 8) b (5 - x)(8 + x) c (5 + x)(8 - x) d (5 - x)(8 - x) S o l u t i o n : c (5 + x)(8 - x) 40+3x-x2=40+8x-5x-x2=8(5+x)-x(5+x)=(8-x)(x+5) Q u e s t i o n : 1 3 4 Tick ? the correct answer: 2x 2 + 5x + 3 = ? a (x + 3)(2x + 1) b (x + 1)(2x + 3) c (2x + 5)(x - 3) d none of these S o l u t i o n : b (x + 1)(2x + 3) 2x2+5x+3=2x2+2x+3x+3=2x(x+1) +3(x+1)=(2x +3) (x+1) Q u e s t i o n : 1 3 5 Tick ? the correct answer: 6a 2 - 13a + 6 = ? a (2a + 3)(3a - 2) b (2a - 3)(3a + 2) c (3a - 2)(2a - 3) d (3a + 1)(2a - 3) S o l u t i o n : c (3a - 2)(2a - 3) 6a2-13a+6=6a2-9a-4a+6=3a(2a-3)-2(2a-3)=(3a-2)(2a-3) Q u e s t i o n : 1 3 6 Tick ? the correct answer: 4z 2 - 8z + 3 = ? a (2z - 1)(2z - 3) b (2z + 1)(3 - 2z) c (2z + 3)(3z - 1) c (z - 1)(4z - 3) S o l u t i o n : a (2z - 1)(2z - 3) 4z2-8z+3=4z2-6z-2z+3=2z(2z-3)-1(2z-3)=(2z-1)(2z-3) Q u e s t i o n : 1 3 7 Tick ? the correct answer: 3 + 23y - 8y 2 = ? a (1 - 8y)(3 + y) b (1 + 8y)(3 - y) c (1 - 8y)(y - 3) d (8y - 1)(y + 3) S o l u t i o n : ) 3+23y-8y2=3+24y-y-8y2=3(1+8y)-y(1+8y)=(3-y)(1+8y) /Read More
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