Question

ajutor dau coroana pls

plsssss​

Answer 1

a) a = 3√32 - 4√27 - 5√72 + 6√108

a = 12√2 - 12√3 - 30√2 + 36√2 = - 18√2 + 24√2

b = 2√243 + 5√50 - 2√75 - 11√8

b = 18√3 + 25√2 - 10√3 - 22√2 = 8√3 + 3√2

a × b =  - 18√2 + 24√2 × 8√3 + 3√2

a × b =  - 18√2 + 192√6 + 3√2 = - 15√2 + 192√6

b) a = √32 - √72 + √128 - √162 + √98 = 4√2 - 6√2 + 8√2 - 9√2 + 7√2

= ( 4 - 6 + 8 - 9 + 7 )√2 =4√2

b = √20 - √45 + √125 - √245 + √80 = 2√5 - 3√5 + 5√5 - 7√5 + 4√5 = √5

a × b = 4√2 × √5 = 4√10

c) a = √48 - √108 + √192 - √243 + √75 = 4√3 - 6√3 + 8√3 - 9√3 + 5√3

= ( 4 - 6 + 8 - 9 + 5 )√3  = 2√3

b = 4√6 - 7√6 + 2√6 - 3√6 + 5√6 = ( 4 - 7 + 2 - 3 + 5 )√6 = 1√6 = √6

a × b = 2√3 × √6 = 2√18 = 6√2