Question

Solve the following

i)(√5+√3)( √5-√3)

ii)( √5+√7)2​

Answer 1

Answer:

i) 2

ii) 2√5+2√7

Step-by-step explanation:

i) (√5+√3)(√5-√3)

using identity (a+b)(a-b)=a²-b²

=(√5)²-(√3)²

=5-3 =2

ii) (√5+√7)2

=2√5+2√7

Answer 2

Step-by-step explanation:

(I). (√5+√3). (√5-√3). (a-b) (a+b) =

${a}^{2} - {b}^{2}$

${ \sqrt{5} }^{2} - { \sqrt{3} }^{2} = 5 - 3 = 2$

(ii). (√5+√7)2.

$(a + b){2} = {a}^{2} + 2ab + {b}^{2}$

${ \sqrt{5} }^{2} + 2 \sqrt{5} \times \sqrt{7} + { \sqrt{7} }^{2}$

=

$5 + 2 \sqrt{35} + 7$