Question

23. Efectuati:
a) (x-5)(3x^2+x+1)+(x^2-1)(-3x+16)
b) (x^2-x+1)(x^2-3x+2)+(x^2+2x+1)(x^2-x+4)
c) (2x^2+x+7)(x-x^2-1)+(x^2+2x+3)(x-2x^2+5)

25. efectuati utilizand regulile de calcul cu puteri:
a) 2^10 * 2^4
b) 7^12 : 7^5
c) (3^4)^6
d) 2^-3
e) (-3)^-4
f) (2/3)^-3

Answer 1

a) (x-5)(3x²+x+1)+(x²-1)(-3x+16)=
= 3x³-15x²+x²-5x+x-5-3x³+3x+16x²-16=
= 2x²-x-21



b) (x²-x+1)(x²-3x+2)+(x²+2x+1)(x²-x+4)=
=x⁴-x³+x²-3x³+3x²-3x+2x²-2x+2+x⁴+2x³+x²-x³-2x²-x+4x²+8x+4=
=2x⁴-3x³+9x²+2x+6=


c) (2x²+x+7)(x-x²-1)+(x²+2x+3)(x-2x²+5)=
=2x³+x²+7x-2x⁴-x³-7x²-2x²-x-7+x³+2x²+3x-2x⁴-4x³-6x²+5x²+10x+15=
=-4x⁴-2x³-7x²+19x+8=


25. efectuati utilizand regulile de calcul cu puteri:
a) 2¹⁰ * 2⁴ =2¹⁴
b) 7¹² : 7⁵=7⁷
c) (3⁴)⁶=3²⁴
d) 2⁻³=1/2³
e) (-3)⁻⁴=1/3⁴
f) (2/3)⁻³=1/(2/3)³=3³/2³