(1) (2) cost means 37 ° 24'36 ''

(1) (2) cost means 37 ° 24'36 ''

(1)48°15′36″ (2)37.41°

F (x) = SiNx + sin (x + 3 / 3 π) (1) the minimum value of the ball f (x) and the set of X when taking the minimum value (2) how can f (x) change from y = SiNx

F (x) = SiNx + sin [x + (π / 3)] = SiNx + [sinxcos (π / 3) + cosxsin (π / 3)] = SiNx + (1 / 2) SiNx + (√ 3 / 2) cosx = (3 / 2) SiNx + (√ 3 / 2) cosx = √ 3 * [(√ 3 / 2) SiNx + (1 / 2) cosx] = √ 3 * sin [x + (π / 6)] (1) therefore, the minimum value of F (x) is - √ 3. In this case, x + (π / 6) = 2K π - (...)

10 out of 11 plus 6 out of 12 plus 5 out of 13 equals

10/11+6/12+5/13
=[2(130+55)+143/]286
=513/286

The next step of Ln (((TaNx SiNx) / (1 + SiNx)) + 1)?
The next step in the answer is (TaNx SiNx) / (1 + SiNx)?

This problem uses the Equivalent Infinitesimal Substitution
When X -- > 0, ln (1 + x) (equivalent infinitesimal)
∵lim(x-->0)(tanx-sinx)/(1+sinx)=0
∴ln(((tanx-sinx)/(1+sinx))+1)~(tanx-sinx)/(1+sinx)

Simple calculation method of 38 × 65 + 62 × 65
Simple calculation method (write out the simple calculation process)

38×65+62×65
=65×（38+62）
=65×100
=6500

Given that the ellipse x ^ 2 / 4 + y ^ 2 = 1, the straight line passing through the left focus F1 intersects the ellipse at points a and B, the trajectory equation of point n in AB is obtained

Let a (x1, Y1), B (X2, Y2), n (x, y), then x = (x1 + x2) / 2, y = (Y1 + Y2) / 2. (1) X1 ^ 2 / 4 + Y1 ^ 2 = 1x2 ^ 2 / 4 + Y2 ^ 2 = 1, subtracting to get: (x1 ^ 2-x2 ^ 2) / 4 + (Y1 ^ 2-y2 ^ 2) = 0, that is, (x1-x2) (x1 + x2) / 4 + (y1-y2) (Y1 + Y2) = 0, dividing both sides (x1-x2), substituting (1) into, simplifying:

If a △ B = 4, then a must be a multiple of B______ (judge right or wrong)

A △ B = 4, because it is not necessarily an integer, such as: 1.6 △ 0.4 = 4; the research scope of factors and multiples is non-zero natural numbers; so the original question is wrong; so the answer is: ×

It is known that the quadratic equation 2x2 + 4x + k-1 = 0 has real roots and K is a positive integer
(1) Finding the value of K
(2) When the equation has two non-zero integer roots, the image of quadratic function y = 2x2 + 4x + k-1 = 0 about X is translated down 8 units, and the analytic expression of the translated image is obtained
(3) Under the condition of (2), the image of the translated quadratic function below the x-axis is folded along the x-axis. When the image y = 1 / 2x + B (B is less than k) has two common points with the image, the value range of B is larger

Discriminant △ = B ^ 2-4ac = 16-4x2 (k-1) ≥ 0 = = > k ≤ 3
So the condition is k ≤ 3
（2）
Y + 8 = 2x2 + 4x + k-1, that is y = 2x2 + 4x + k-1-8 = 2x2 + 4x + K-9
(3) Let y = 2x2 + 4x + K-9 = 0. The small value of solution x 1 = - 1 - (16-8 * (K-9)) ^ 0.5/4, let y '= 4x + 4 = 1 / 2 (the same slope), then x 2 = - 7 / 8
Taking X1 and into 1 / 2x + B = 0 respectively, the two values of B (upper and lower limits) B1 and B2 are obtained, and then combined with the condition B

If you divide a decimal by 0.01, you will enlarge the decimal to 100 times the original______ (judge right or wrong)

If you divide a decimal by 0.01, you will enlarge the decimal to 100 times the original

To solve the equations: 3x − 4Y = 105x + 6y = 42

3x − 4Y = 10 & nbsp; & nbsp; ① 5x + 6y = 42 & nbsp; & nbsp; ②, ① × 5 - ② × 3 get - 38y = - 76, y = 2, substitute into ① get: 3x-8 = 10, x = 6. Then the solution of the original equations is x = 6y = 2