Let the equation x = y Λ y determine that y is a function of X and find dy

Let the equation x = y Λ y determine that y is a function of X and find dy

ylny = lnx
Two sides of X are derived
y'lny + y(1/y)y' = 1/x
y'lny + y' = 1/x
(lny + 1)y' = 1/x
y' = 1/[x(lny + 1)]

Find the derivative or partial derivative of the function determined by the following equations: z = x Λ 2 + y Λ 2 x Λ
Find the derivative or partial derivative of the function determined by the following equations: z = x Λ 2 + y Λ 2 x Λ 2 + 2Y Λ 2 + 3Z Λ 2 = 20 find dy / DX DZ / DX

Merge similar items and simplify yourself. The screen of netbook is too small to help you simplify and merge similar items
  

Sin9o =?, cos90 =?, tan90 =? Sin180 =?, cos180 =?, tan180 =?

Sin9o = 1, cos90 = 0, tan90 = nonexistent
Sin180 = 0, cos180 = - 1, tan180 = 0

Sum: 1 / 1 * 3 + 1 / 2 * 4 + 1 / 3 * 5 + 1 / 4 * 6 + ~ + 1 / N (n-1)

First of all, should the title be: 1 / 1 * 3 + 1 / 2 * 4 + 1 / 3 * 5 + 1 / 4 * 6 + ~ + 1 / N (n-2)
1 / 1 * 3 + 1 / 2 * 4 + 1 / 3 * 5 + 1 / 4 * 6 + ~ + 1 / N (n-2) can be reduced to:
1/2(1-1/3+1/2-1/4+1/3-1/5+~+1/（n-2）-1/n)
So the sum is:
1/2(1+1/2-1/(n-1)-1/n)

Is there any supplementary explanation for the function of dash?

A dash (--) is a symbol indicating the change of topic or mood, the continuation of voice, etc. "the sentences explained in the text are marked with a dash." "the sudden change of topic is marked with a dash." "the voice is extended, and a dash is used after the onomatopoeia." "the items are listed and divided, and a dash is used before each item." "the

Given that F1 and F2 are the two focal points of the ellipse x2a2 + y2b2 = 1 (a > b > 0), and ab is the chord passing through F1, then the perimeter of △ abf2 is ()
A. 2aB. 4aC. 8aD. 2a+2b

∵ F1, F2 are the two focal points of the ellipse x2a2 + y2b2 = 1 (a > b > 0), AB is the chord passing through F1, the perimeter of ∵ abf2 = | AF1 | + | af2 | + | BF1 | + | BF2 | = 2A + 2A = 4A

The circumference of a rectangle is 120 decimeters, and its width is 23 decimeters. What is the area of the rectangle?

120 △ 2 = 60 (decimeter) 60 × 22 + 3 = 24 (decimeter) 60-24 = 36 (decimeter) 24 × 36 = 864 (square decimeter) answer: the area of this rectangle is 864 square decimeter

Evaluation: sin26 π 3 + cos (− 17 π 4)=______ ．

∵ sin26 π 3 + cos (- 17 π 4) = sin (9 π - π 3) + cos (4 π + π 4) = - sin (π + π 3) + cos π 4 = sin π 3 + cos π 4 = 3 + 22

The equation (2m-1) x2-8x + 4 = 0 of X has real roots, so we can find the value range of M

In the equation (2m-1) x2-8x + 4 = 0 of X, a = 2m-1, B = - 8, C = 4; if the equation has real roots, then △ = b2-4ac = (- 8) 2-4 (2m-1) × 4 ≥ 0, the solution is m ≤ 52; therefore, the value range of M is m ≤ 52

If f (x) satisfies f (x + 1) = f (x) + 1 and f (100) = 101, then f (1) is equal to____ .

2
f(100)=f(99)+1=101
So f (99) = 100
So f (1) = 2