Question

8. Factorise :
(i) (a – 3b)2 - 36 b2
(ii) 25(a - 5b)2 – 4(a – 3b)2
(iii) a2 - 0-36 62
(iv) a4 - 625
(v) x4 - 5x2 - 36
(vi) 15(2x - y)2 - 16(2x - y) - 15
9. Factorise ab - b3. Using this result, find the
value of 1012 x 100 - 1003
10. Evaluate (using factors) : 3012 x 300 - 3003.​

Answer 1

Answer:

8(i)Factor (a−3b)(2)−36b2

−36b2+2a−6b

=2(−18b2+a−3b)

(ii)25(a−5b)(2)−4(a−3b)(2)

42a−226b

=2(21a−113b)

(iii)Factor a2−0−(36)(62)

=a2−2232

Doesn't factor

Answer:

a2−2232

(iv)Factor a4−625

a4−625

=(a2+25)(a+5)(a−5)

(v)Factor x4−5x2−36

x4−5x2−36

=(x2+4)(x+3)(x−3)

(vi)Factor 15(2x−y)(2)−16(2x−y)−15

Cannot factor