Question

2 la puterea n inmultit cu 5 la puterea n-1 egal 2000 cat este n?

Answer 1

2ⁿ * 5ⁿ⁻¹ = 2000 ⇒2ⁿ * 5ⁿ/5 = 2000 ⇒2ⁿ * 5ⁿ = 10000 ⇒ 10ⁿ = 10⁴ ⇒n= 4

Answer 2

2^n × 5^n-1 = 2 000

2^n × 5^n : 5 = 2 000 |× 5

(2 × 5)^n = 5 × 2 000

10^n = 10 000

10^n = 10^4

n = 4
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