Question

please solve this question

Answer 1

19a)(X+a)(X+b)=X^2+(a+b)X+ab
19b)(1000-4)^2. (a-b)^2
( 1000)^2+(4)^2-2(1000)(4)
1000000+16-8000
992016
I hope this will help you


20a)
Consider, 27x3 + y3 + z3 - 9xyz               = (3x)3 + y3 + z3 - 3 × (3x) × y × z                 = [3x + y + z ][(3x)2 + y2 + z2 - (3x) × y − y × z  − z(3x)] [Since  (a + b + c )(a2 + y2 + z2 - ab−bc−ca)]               = [3x + y + z ][9x2 + y2+ z2 - 3xy − yz  − 3zx]


I hope this will help you

the last question is in complete I think

Answer 2

Hope this helps you
Mark my answer as brainliest