Using prime factorization method , find the HCF b)18 and 15
c)16 ,32 and 48
e)27, 63 and 54

see explanation

Step-by-step explanation:

(b)

18 = 2 × 3 × 3 = 2 × 3²

15 = 3 × 5

The common prime factor = 3

HCF = 3

(c)

16 = 2 × 2 × 2 × 2 =

32 = 2 × 2 × 2 × 2 × 2 =

48 = 2 × 2 × 2 × 2 × 3 = × 3

The common prime factor =

HCF = = 16

(e)

27 = 3 × 3 × 3 = 3³

63 = 3 × 3 × 7 = 3² × 7

54 = 2 × 3 × 3 × 3 = 2 × 3³

The common prime factor = 3²

HCF = 3² = 9

- 2 + 10x³ - 21x² + 19x - 4

step-by-step explanation:

each term in the second factor is multiplied by each term in the first factor

x²(- 2x² + 4x - 1) - 3x(- 2x² + 4x - 1) + 4(- 2x² + 4x - 1) ← distribute

= - 2 + 4x³ - x² + 6x³ - 12x² + 3x -8x² + 16x - 4

collect like terms

= - 2 + 10x³ - 21x² + 19x - 4 ← in standard form