Question

care ma ajuta cu exercițiile si sa imi explice rezolvarea​

Answer 1

Răspuns:

Explicație pas cu pas:

$a)~~~x=\sqrt{3^{2}+4^{2}} *\sqrt{3^{2}*4^{2}}=\sqrt{9+16} *\sqrt{3^{2}}*\sqrt{4^{2}}=\sqrt{25}*3*4=5*3*4=60\\ b)~~y=(\sqrt{4*3}+\sqrt{16*3}+\sqrt{9*3})*\dfrac{1}{\sqrt{3} }=(2\sqrt{3}+4\sqrt{3}+3\sqrt{3})*\dfrac{1}{\sqrt{3} }=9\sqrt{3}* \dfrac{1}{\sqrt{3} }=9$

(x+y+z):3=30, ⇒x+y+z=30·3, ⇒60+9+z=90, ⇒z=90-69=21.

Ex5. E(x)=(4-5x)²-2(8x²-30x+25)+(2x-5)²=16-40x+25x²-16x²+60x-50+4x²-20x+25=13x²-9

E(-x)=13·(-x)²-9=13x²-9=E(x).