#9th maths

In this post 9th Maths Quiz 2 you can get plenty of one word questions for the standard of 9. I made these questions for only 9th annual 2024 perspective. These collections of questions are engaging you in a proper way. These test will help you to score more marks in your all exams. If you want explanation video of each and every questions, you will go through our YouTube chennal –…

FACTORIZATION – EXERCISE 3.2.6 – Class 9

Factorise (i) a3 – b3 – c3 – 3abc Solution: = a3 + (– b3)+(– c3) – 3a(–b) ( –c) Using x3 + y3 + z3 – 3xyz = (x + y +z) (x2 + y2 + z2 – xy – yz – xz) we get x = a y = –b c = –c ∴ a3 + (– b3)+(– c3) – 3a(–b) (c) = [a + (–b) +(c)] [a2 + (–b)2 + (–c) – a(–b) (–b)(–c) – (–c)a] = (a – b – c) (a2 + b2 + c2 + ab – bc + ca)   (ii) a3 – b3 + 8c3 + 6abc Solution: Using x3 + y3 + z3 – 3xyz = (x + y +z) (x2 +…

FACTORIZATION – EXERCISE 3.2.5 – Class 9

Factorise: (i) 8y3 – 1 Solution: = (2y)3 – 13 [∵ a3 – b3 = (a – b) (a2 + ab + b2)] = (2y – 1) [(2y)2 + 2y .1 + 12] = (2y – 1) (4y2 + 2y + 1)   (ii) 27x3 – 8 Solution: = (3x)3 – 23 [∵ a3 – b3 = (a – b) (a2 + ab + b2)] = (3x – 2) [(3x)2 + 3x .2 + 22] = (3x – 2) (9x2 + 6x + 4)   (iii) x3 + 8y3 Solution: = x3 + (2y)3 [∵ a3 + b3 = (a + b) (a2 – ab + b2)] = (x + 2y) [x2 – x.2y + (2y)2] = (x + 2y) (x2 –…

FACTORIZATION – EXERCISE 3.2.4 – Class 9

Resolve into factors (i) x4 + y4 – 7x2 y2 Solution: = x4 + y4 – 2x2 y2 – 2x2 y2 – 7x2 y2 = x4 + y4 + 2x2 y2 – 9x2 y2 = (x2 + y2)2 – (3xy)2 = (x2 + y2 + 3xy) (x2 + y2 – 3xy)   (ii) 4x4 + 25y4 + 10x2y2 Solution: Take a = √2x ;b = √5y a4 + b4 + a2 b2 = (a2 + b2 + ab) (a2 + b2 – ab) 4x4 + 25y4 + 10x2y2 = (√2 x)4 + (√5 y)4 + 2 x2 5 y2 = [( 2 x2) + ( 5 y2) + (√10 xy] [( 2 x2) + ( 5 y2) – (√10 xy] =…

Factorization – EXERCISE 3.2.3 – Class 9

Factorize (i) x2 + 9x + 18 Solution: = x2 + 6x + 3x + 18 = x (x + 6) + 3 (x + 6) = (x + 6) (x + 3)   (ii) y2 + 5y – 24 Solution: = y2 + 8y – 3y – 24 = y (y + 8) – 3 (y + 8) = (y + 8) (y – 3)   (iii) 7y2 + 49y +84 Solution: = 7 (y2 + 7y + 12) = 7 (y2 + 4y + 3y + 12) =7 [y (y + 4) + 3 (y + 4)] =7 (y + 4) (y + 3)   (iv) 40 + 3x – x2 Solution: = – [x2 – 3x – 40] = 3 – [x2 – 8x + 5x – 40] = – [x (x –…

FACTORIZATION – EXERCISE 3.2.1 – Class 9

Factorise: (i) 5x2 – 2xy Solution: = 5x(x – 4y)   (ii) 2p(x + y) – 3q(x + y) Solution: = (x + y) (2p – 3q)   (iii) 4(a + b)2 – 6(a + b) Solution: = 2 (a + b) [2(a + b) – 3] = 2 (a + b) (2a + 2b – 3)   (iv) 18x2y – 24xyz Solution: = 6xy (3x – 4z)   (v) 7xa – 70 xb Solution: = 7x (a – 10b)   (vi) 13m2 + 156n2 Solution: =13(m2 + 12n2)   (vii) 3x2 + 6x +6 Solution: = 3 (x2 + 2x + 2)   (viii) 4abx2 +…

HCF AND LCM – EXERCISE 3.3.4 – Class 9

Find the LCM of the following: (i) 2x + 6, x2 + 3x Solution: 2x + 6 = 2 (x + 3) x2 + 3x = x (x + 3) LCM = 2x (x + 3)   (ii) x2y + xy2, x 2+ xy Solution: x2y + xy2 = xy (x + y) x 2+ xy = x ( x+ y) LCM = xy (x + y)   (iii) 3x2 – 75, 2x3 + 250 Solution: 3x2 – 75 = 3 (x2 – 25) = 3 (x2 – 52) = 3 (x + 5) (x – 5) 2x3 + 250 = 2 (x3 + 125) LCM = 2 x 3 (x + 5) (x3 + 125) = 6 (x + 5) (x3 + 125)   (iv) a2 –…