Вариант 21 ИДЗ 6.2

DHS - 6.2
Find y´ and y. "
№ 1.21. y² = x + Ln (y / x).
Find y´ and y. "
No. 2.21. {x = Lnt / t; y = t²Lnt.
No. 3.21. For a given function y and argument x0, calculate y ‴ (x0); y = x²cos x; x0 = π / 2.
No. 4.21. Write the formula for the derivative of the nth order for the function y = cos 3x;
No. 5.21. Find the points on the curve y = x³ / 3 - 9x² / 2 + 20x - 7; in which the tangent is parallel to the axis Ox.
No. 6.21. On the Ox axis two material points move the laws of motion of which x = 5t² + 2t + 6 and x = 4t² + 3t + 18. With what speed do these points move away from each other at the time of the meeting?