What is the function of differential and integral for symbolic expression in MATLAB?

What is the function of differential and integral for symbolic expression in MATLAB?

1. The function of integral is int (function name, left end of integral interval, right end of integral interval). If the latter two are not filled in, it is considered as indefinite integral
2. The function diff (y, x, K) of derivative means that y is the K derivative of X. basically, the meaning of derivation and differentiation is the same

The differential of y = LNX function

dy=(1/lnx)*(lnx)' dx
=(1/lnx)*(1/x) dx
=1/(xlnx) dx

Find the differential of this function y = sinxy

y=sin（xy）
dy=d(xy)*cos(xy)
=(ydx+xdy)cos(xy)
dy-(xcos(xy))dy=ydx
dy=y/[1-xcos(xy)] dx

Equation contains addition formula, sub equation contains subtraction formula, sub equation contains multiplication formula, sub equation contains division formula]

X + 5 = 27 (the equation contains addition)
A-5 = 5 (the equation contains subtraction)
B * 6 = 42 (equation contains multiplication)
Y △ 7 = 5 (the equation contains Division)

A two digit number can be divided by 3 and 5 at the same time. If the number is odd, the maximum is (). If the number is even, what is the maximum
don't quite understand

The odd maximum is 75 and the even maximum is 90

Three out of two plus zero 2x minus two out of one plus zero 03x equals 0.75

3/0.2+0.2x-0.2/0.01+0.03x=-0.75
0.5x=0.75-(3/0.2-0.2/0.01)
x=0.75+5
=5.75/0.5
=11.5

First simplify, then evaluate: 4 (a2-5a + b) - 3 (a2-6a-3b2), where a = - 3, B = - 2

The original formula = 4a2-20a + 4b-3a2 + 18a + 9b2 = a2-2a + 4B + 9b2, when a = - 3, B = - 2, the original formula = 9 + 6-8 + 36 = 43

5. 6, 7, 8, 9, 10, 11, 12, 13 each horizontal line, each vertical line, each diagonal line add up to 27
Urgent need

6 13 8
11 9 7
10 5 12

Solving the equations 2x-y + 2Z = 6 3x + y-3z = - 4 x + y + Z = 6

2x-y+2z=6 (1)
3x+y-3z=-4 (2)
x+y+z=6 (3)
(1)+(2)
5x-z=2 (4)
(1)+(3)
3x+3z=12
x+z=4 (5)
(4)+(5)
6x=6
x=1
z=4-x=3
y=2x+2z-6=2

5 + 3 = 28 9 + 1 = 810 8 + 6 = 241 5 + 4 = 11 what is 7 + 3

410
7-3=4,7+3=10