Question

imd va rogggggggggg

Answer 1

Răspuns:

Explicație pas cu pas:

a = 4/(√20 + √12) + √3 - 1 = 4/(2√5 + 2√3) + √3 - 1

= 2/(√5 + √3) + √3 - 1 = 2(√5 - √3)/(√5 + √3)(√5 - √3) + √3 - 1

=2(√5 - √3)/(5 - 3) + √3 - 1 = √5 - √3 + √3 - 1 = √5 - 1

a = √5 - 1

____________

b = 6/(2√8 - √20) - √8 + 1 = 6/(4√2 - 2√5) - 2√2 + 1

= 3/(2√2 - √5) - 2√2 + 1 = 3(2√2 + √5)/(2√2 - √5)(2√2 + √5) - 2√2 + 1

= 3(2√2 + √5)/(8 - 5) - 2√2 + 1 = 2√2 + √5 - 2√2 + 1 = √5 + 1

b = √5 + 1

_____________

Ma = (a + b) : 2 = (√5 - 1 + √5 + 1) : 2 = 2√5 : 2 = √5

____________

a*b = (√5 - 1)(√5 + 1) = 5 - 1 = 4

Mg = √4 = 2