Question

13. Determinați soluțiile ecuațiilor următoare: ​

Answer 1

Poftim !sper ca este bine

Answer 2

Răspuns:

a)

$x^2+3^2=5^2\\x^2=5^2-3^2\\x^2=25-9\\x^2=16\\x=+-\sqrt{16}\\\x=+-4$

b)

$25^2-x^2=7^2\\25^2-x^2-7^2=0\\x^2=25^2-7^2\\x^2=18*32\\x=+-\sqrt{576}\\ x=+-24$

c)

$13+2x^2=x^2-12\\13+2x^2-x^2+12=0\\x^2+25=0\\x^2=-25\\x=+-\sqrt{25} \\x=+-5$

d)

$\frac{x}{2}=\frac{4-3x-x^2}{2x-6} (inmultim /pe/ diagonala)\\x(2x-6)=2(4-3x-x^2)\\2x^2-6x=8-6x-2x^2\\2x^2+6x-8+6x+2x^2=0\\4x^2-8=0$

$x^2=\frac{8}{4} \\x^2=2\\x=+-\sqrt{2}$

f)

$\frac{2x}{1}=\frac{x^2-1}{x}(inmultim/pe /diagonala )\\2x*x=1*(x^2-1)\\2x^2=x^2-1\\2x^2-x^2+1=0\\x^2=-1\\x=+-\sqrt{1}\\ x=+-1$

Explicație pas cu pas: