NCTB Class 8 Math Chapter Five Exercise 5.1 Solutions by Math Expert. Bangladesh Board Class 8 Math Solution Chapter Five Algebraic Fractions Exercise 5.1 Solution.
|
Board |
NCTB |
| Class |
8 |
|
Subject |
Mathematics |
| Chapter |
5 |
|
Chapter Name |
Algebraic Fractions |
| Exercise |
5.1 Solution |
Exercise 5.1
1> Algebraic fractions :
(a) 4x2y3z5/9x5y2z3
= 4/9 . yz2/x3
= 4yz2/9x3
(b) 16(2x)4(3y)5/(3x)3.(xy)6
= 36x/y
(c) x3y+xy3/x2y3+x3y2
= xy (x2+y2) /x2y2(y+x)
= x2+y2/xy(x+y)
(d) (a-b)(a+b)/a2-b3
= (a-b)(a+b) / (a-b)(a2+ab+b2)
= (a+b)/a2+ab+b2
(e) x2-6x+5/x2-25
= x2-5x-x+5/x2-52=
= x(x-5)-1(x-5)/(x+5)(x-5)
= (x-1)(x-5)/(x+5)(x-5)
= (x-1)/(x+5)
(f) x2-7x+12/x2-9x+20
= x2-4x-3x+12/x2-5x-4x+20
= x(x-4)-3(x-4)/x(x-5)-4(x-5)
= (x-3)(x-4) / (x-5)(x-4)
= x-3/x-5
(g) (x3-y3) (x2-xy+y2)/(x2-y2) (x3+y3)
(h) a2-b2-2bc-c2/a2+2ab+b2-c2
(h) x-y/x+y, y-z/y+z, z-x/z+x
2> express the following fractions in the form of a common denominator:
(a) x2/xy , y2/yz, z2/zx
(b) x-y/xy, y-z/yz, z-x/zx
(d) x+y/(x-y)2, x-y/x3+y3, y-z/x2-y2
(e) a /a3+b3, b/(a2+ab+b2), c/(a3-b3)
(g) a-b/a2b2, b-c/b2c2, c-a/c2a2
(h) x-y/x+y, y-z/y+z, z-x/z+x
3> Find the sum:
(a) a-b/a + a+b/b
(b) a/bc + b/ca + c/ab
(c) x-y/x + y-z/y + z-x/z
(d) x+y/x-y + x-y/x+y
(e) 1/x2-3x+2 + 1/x2-4x+3 + 1/x2-5x+4
(f) 1/a2-b2 + 1/a2+ab+b2 + 1/a2-ab+b2
4>
(a) a/x-3 – a2/x2-9
(b) 1/y(x-y) – 1/x(x+y)
(c) x+1/1+x+x2 – x-1/1-x+x2
(d) a2+16b2/a2-16b2 – a-4b/a+4b
5>
(a) x-y/xy + y-z/yz + z-x/zx
(b) x-y/(x+y)(y+z) + y-z/(y+z)(z+x) + z-x/(z+x)(x+y) .
(c) y/(x-y)(y-z), x/(z-x)(x-y), z/(y+z)(z+x)
(d) 1/(x+3y) + 1/x-3y – 2x/x2-9y2
(f) 1/x-2 – x-2/x2+2x+4 + 6x/x3+8
(g) 1/x-y – 1/x+1 – 2/x2+1 + 4/x4+1
(h) x-y/(y-z)(z-x) + y-z/(z-x)(x-y) + z-x/(x-y)(y-z)
(i) 1/a-b-c + 1/a-b+c + a/a2+b2-c2-2ab
