А1.
(√(6-t) + √(5-t))² =4²
6-t+2√[(6-t)(5-t)]+5-t=16
2√(30-5t-6t+t²)=2t+16-11
(2√(t²-11t+30))²=(2t+5)²
4(t²-11t+30)=4t²+20t+25
4t²-4t²-44t-20t=25-120
-64t=-95
t=95/64
√(6-t) - √(5-t)=√(6 - ⁹⁵/₆₄) - √(5 - ⁹⁵/₆₄)=√(²⁸⁹/₆₄) - √(²²⁵/₆₄)=
= ¹⁷/₈ - ¹⁵/₈ = ²/₈ = ¹/₄ = 0.25
Ответ: 1)
А2.
[5(x+2)+1]/[(x+2)-4] - [5(x+6)+1]/[(x+6)-4]=
=(5x+10+1)/(x-2) - (5x+30+1)/(x+2)=
=(5x+11)(x-2) - (5x+31)/(x+2) =
=[(5x+11)(x+2)-(5x+31)(x-2)]/(x² -4)=
=(5x²+11x+10x+22-5x²-31x+10x+62)/(x² -4)=
=84/(x² -4)
Ответ: 1)