Question

Q1) Use the identity (x + a) (x + b) = x2 + (a + b) x + ab to find the following products.





(i) (x - 5) (x - 1)​

Answer 1

Answer :

$(i) \sf \: (x - 5)(x - 1)$

$\sf(using \: identity): (x + a)(x + b) = {x}^{2} + (a + b)x + ab$

$\sf(x - 5)(x - 1) = {(x)}^{2} + [( -5 )+ ( - 1)] x + ( \cancel - 5) \times ( \cancel- 1) \\ \\ \sf\huge = {x}^{2} - 6x + 5$

Answer 2

$\Huge\mathfrak\red{answer:}$

$\sf{ }$

$\large\bf{{\underline{To~solve}}:}$

$\tt{~~~~~~(x-5)(x-1)}$

$\bf{Using~the~identity:}$

$\tt{~~~~~~(x+a)(x+b)=x^{2}+(a+b)x+ab}$

$\tt{:→ (x)^{2}+[(-5)+(-1)~]x+[(-5)×(-1)~]}$

$\tt{:→ x^{2}+(-6)x+5}$

$\tt{:→ {\red{\underline{\boxed{\bf x^{2}-6x+5}}}}}$