Question

3
17. Factorise : (x2 – 3x) (x2-3x - 1) - 20.​

Answer 1

Answer:

Factorisation by grouping the terms: (x2+3x)2-5(x2+3x)-y(x2+3x)+5y. check- ... 2.7 K+. 54.3 K+. 2:17. Factorize each of the following expressions : (i) `a^3 + a. play ... 7.0 K+. 142.2 K+. 1:54. Solve for `x` and `y : 3x^2-5y^2. play. 251865. 44.9 K+.

Missing: 20 ‎| Must include: 20

Step-by-step explanation:

Answer 2

Answer:

Question :-

➠ (x² - 3x) (x² - 3x - 1) - 20

Answer :-

➠ (x² - 3x) (x² - 3x - 1) - 20

➻ (x² - 3x) {(x² - 3x) - 1} - 20

➻ (p) {(p) - 1} - 20 [Taking x² - 3x = p]

➻ p² - p - 20

➻ p² - (5 - 4)p - 20

➻ p² - 5p + 4p - 20

➻ p(p - 5) + 4(p - 5)

➻ (p - 5) (p + 4)

➻ (x² - 3x - 5) (x² - 3x + 4) [ Putting value of p = x² - 3x]

∴ The value of (x² - 3x) (x² - 3x - 1) - 20 is (x² - 3x - 5) (x² - 3x + 4)