Question

Sa se calculeze:
a)(x+3)totul la puterea a 2 -x(x+1)+2
b)(-72x la puterea 5 +48xla puterea 4-36x la puterea 3):(-4xla puterea 2)
c)21xla puterea 3-14xla puterea2):-(7xla puterea 2)+(x-1)(x+2)

Answer 1

(x+3)²-x(x+1)+2 = x²+2×x×3+3² -2x-x+2=x²+6x+9-3x+2=x²+3x+11

Answer 2

a) = $x^{2} +3x+3x+9-( x^{2} +x)+2=x^{2} +6x+9-( x^{2} +x)+2=5x+9+2=5x+11$

b) = $18x^{3}-12 x^{2} +9x$

c) = $(21x^{3} - 14x^{2})/ 7x^{2} +(x*x+x*2+-3*2= (21x^{3}-14 x^{2} ) /7 x^{2} + ( x^{2} +2x-3x-6)=3x-2+( x^{2} +2x-3x-6)=3x-2+( x^{2} -x-6)= x^{2} +2x-8=(x+4)*(x-2)$