Question

1) Factorise: 40x³-135 using appropriate identities

Answer 1

Answer:

x=1.5 and x=-1.5

Step-by-step explanation:

40x³-135=0

40x³=135

x³=135/40

x=± ³√3.375

x=±1.5

x=1.5. and x=-1.5

Answer 2

Given,

Equation:  40x³-135

To Find,

Factorized form of given equation =?

Solution,

Equation : 40x³-135

Taking 5 common, we get

⇒5(8x³ - 27)

⇒5[(2x)³  - 3³]

Using a³ - b³ = (a - b) (a² + ab + b²), we have

⇒5[(2x - 3)((2x)² + 2x*3 + 3²)]

⇒5(2x - 3)(4x² + 6x + 9)

Hence, the factorized form of 40x³-135 is 5(2x - 3)(4x² + 6x + 9)