Question

Заранее 1. (t-8)²-t(t-6) при t= -1,5 2. (3t+2)²-4(3t+1) при t= - 2/3 3. (6t+1)²-(1-6t)² при t= -3/4

Answer 1

1.(t-8)^2-t(t-6)=t^2-16t+64-t^2+6t=-16t+64+6t=-10t+64=-10*(-1,5)+64=
=15+64=79;
2.(3t+2)^2-4(3t+1)=9t^2+12t+4-12t-4=9t^2=9*(-2/3)^2=9/1*4/9=4/1=4;
3.(6t+1)^2-(1-6t)^2=36t^2+12t+1-1+12t-36t^2=12t+12t=24t=24*(-3/4)=
=24/1*(-3/4)=-18/1=-18.

Answer 2

1) (t-8)2 - t(t-6) = (t-8)2 - (t2 - 6t) = t2 - 16t + 64 - t2+6t = 64-10t
при t=-1,5
64-10*(-1,5)=79
2)(3t+2)2 - 4(3t+1) = 9t2 + 12t + 4 - 12t - 4=9t2
при t=-2/3
9*(-2/3)2=9*4/9=4
3)(6t+1)2-(1-6t)2=36t2+12t + 1 - (1-12t+36t2) =36t2 +12t +1-1+12t-36t2=24t
при t=-0,75
24*(-0,75)=-18