Question

ajutati maaa la ex 2 si 3​

Answer 1

Răspuns:

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➋ a) x² = 9 <=> 3² = 9 <=> 9 = 9 Ⓐ

b) 7x² = 63 <=> 7 • 3² = 63 <=> 7 • 9 = 63 <=> 63 = 63 Ⓐ

c) (x - 1)² = 4 <=> (3 - 1)² = 4 <=> 3² - 2(3 • 1) + 1² = 4 <=>

<=> 9 - 6 + 1 = 4 <=> 3 + 1 = 4 <=> 4 = 4 Ⓐ

d) (2x + 1)² = 49 <=> (2 • 3 + 1) = 49 <=> (6 +1)² = 49 <=>

<=> 7² = 49 <=> 49 = 49 Ⓐ

a) x² = 4 <=> (-2)² = 4 <=> 4 = 4 Ⓐ

b) 5x² = 20 <=> 5 • (-2)² = 20 <=> 5 • 4 = 20 <=>

<=> 20 = 20 Ⓐ

c) (x - 1)² = 9 <=> (-2 - 1)² = 9 <=> (-3)² = 9 <=> 9 = 9 Ⓐ

d) (2x - 1)² = 25 <=> [2 • (-2) -1]² = 25 <=> (-4 -1)² = 25 <=>

<=> (-5)² = 25 <=> 25 = 25 Ⓐ

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la 3 nu prea știu, dar sper că te-am ajutat