Odpowiedź:
1) 5a-2(3a-7) =
= 5*(-1)-2*3a-2*(-7) =
= -5-6a+14=
= -6a+14-5 =
= -6a+9 =
= -6*(-1)+9 =
= 6+9 =
= 15
2) c- (x²/2) =
= 1/2- (x²/2) | *2 =
= 1/2*2- (x²/2*2) =
= 1-x²
3) (2a-6)*(7+2a) =
= [2*(-1)-6]*[7+2*(-1)] =
= (-2-6)*[7+(-2)] =
= -8*(7-2) =
= -8*5 =
= -40
4) -a+[a²-b²/4] =
= -1+[(-1)²- (1/2)²]/4 =
= -1+[(1-1/4)/(4)] =
= -1+[(3/4)/(4)] |*4=
= -1*4+[(3/4)/(4)]*4 =
= -4+3/4 =
= -3 1/4
