<span> 7m−11n, если m=−411, n=47.
7*(-411)-11*(47)= -2877 - 517= - 3394</span>
-4x^2+4x-4x+4=0
-4x^2+4=0
4x^2-4=0
4x^2=4
x=+1, -1
Ответ: x=1, x=-1
1)tgt/2=sint/(1+cost)
sin2t/(1+cos2t) *cost/(1+cost)=2sintcost*cost/2cos²t(1+cost)=sint/(1+cost)=tgt/2
2)sin2t/(1+cos2t)*cost/(1+cost)*cost/2/(1+cost t/2)=tgt/2*<span>cost/2/(1+cost t/2)=</span>
=sint/2*cost/2/cost/2*(1+cost/2)=sint/2/(1+cost/2)=tgt/4