Question

RAZOLVATI IN R ECUATIA (URGENT)

a) (x-1)2(la patrat) + (x+2)2(la patrat) - (x-2)(x+2) = 24.
b) (x-2)2(la patrat) + (x+1)2(la patrat) - (x-1)(x+1) = 14.

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30de punce O_O
Coronica (poate ca)
5 stele
Pa patanski in spun multumesc

Answer 1

Răspuns:

Explicație pas cu pas:

$a) (x-1)^{2} + (x+2)^{2}  - (x-2)(x+2) = 24\\\\x^{2} - 2x + 1 + x^{2} + 4x + 4 - (x^{2}-4) = 24\\\\x^{2} - 2x + 1 + x^{2} + 4x + 4 - x^{2}+4 = 24\\\\-x^{2} + 2x + 9 = 24\\\\- x^{2} + 2x - 13 = 0|*(-1)\\\\x^{2} - 2x + 13 = 0\\\\\D = (-2)^{2} - 4(1)(13)\\  D = - 48$

Solutia: nu are(multime vida)

$(x-2)^{2}  + (x+1)^{2}  - (x-1)(x+1) = 14\\\\x^{2} -4x + 4 + x^{2} +2x + 1 - x^{2} + 1 = 14\\\\x^{2} - 2x - 8 = 0\\\\(x-4)(x-2) = 0\\x_{1} = 4\\x_{2} = 2$