Can 32 + 89 + 18 = () be simplified

Can 32 + 89 + 18 = () be simplified

Energy 32 + 18 = 50 50 + 89 = 139

Let f (x) = x ^ 2-2ax + 2, when x belongs to [1,2], find the function range

F (x) = x ^ 2-2ax + 2 = (x-a) ^ 2 + 2-A ^ 2, the axis of symmetry is x = a (the following is divided into the axis of symmetry x = a, which is discussed on the left, middle and right sides of the interval [1,2], and can be combined according to the number and shape of the function image)
(1) When a

As shown in the picture, ABCD is a rectangular lawn, 20 meters long and 14 meters wide, with a zigzag path 2 meters wide in the middle

The area of the path is (20 + 14) × 2 - 2 × 2 = 64 square meters

Choose any number from 1,2,3, --, 9, multiply this number by 3, and then multiply the result by 37037. What rule do you find?

37037*3=111111

In the sequence {an}, it is known that for any positive integer n, there is an n-th power-1 of a1 + A2 +... + an = 2, then the square of a1 + the square of A2 +... + an is equal to
（）
A. The square of (2 to the nth power - 1) is 1 / 3 of the square of (2 to the nth power - 1)
C. The nth power of 4-1 D. (the nth power of 4-1) is 1 / 3 of the square

When Sn = a1 + A2 +... + an = 2 ^ N-11. N = 1, A1 = S1 = 2-1 = 12. N > = 2, an = SN-S (n-1) = 2 ^ n-2 ^ (n-1) = 2 ^ (n-1), A1 = 1, so an = 2 ^ (n-1) sequence is equal ratio sequence of A1 = 1, q = 2, then an ^ 2 = 4 ^ (n-1), {an ^ 2} is equal ratio sequence of A1 ^ 2 = 1, q = 4, so TN = A1 ^ 2 +... + an ^ 2 = 1 * (1-4 ^

Granny Wang's house decoration, with an area of 9 square decimeters of brick floor to use 160, if you use 4 decimeters of brick floor, how many? (solve by proportion)

If x blocks are used to pave the floor with square bricks with side length of 4 decimeters, then: (4 × 4) × x = 160 × 9, & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; 16x = 1440, & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; X = 1440 △ 16, & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; X = 90

9 out of 10 times 5 out of 6 minus 3 out of 2

9 out of 10 times 5 out of 6 minus 3 out of 2
=3 / 4-3 / 2
=-3 / 4

Trigonometric function solution (1-sin2a + cos2a) / (1-sin2a-cos2a)
Please help as soon as possible. Thank you

(1-sin2a + cos2a) / (1-sin2a-cos2a) = (sin ^ 2A + cos ^ 2a-2sinacosa + cos ^ 2a-sin ^ 2a) / (sin ^ 2A + cos ^ 2a-2sinacosa-cos ^ 2A + sin ^ 2a) = [(Sina COSA) ^ 2 - (Sina + COSA) (Sina COSA)] / [(Sina COSA) ^ 2 + (Sina + COSA) (Sina COSA)] = (Sina COSA) / [(Sina COSA) 2sina] = - cosa / Sina = - COTA cannot be equal to 2n π + π

On the drawing scale of 1:500, the area of a rectangular grassland is 6 square centimeters

1: The length ratio is 1:500 and the area ratio is 1:500x500
The area of a rectangular grassland is 6 square centimeters, and the actual area is 6x500x500 = 1.5 million square centimeters
=150 square meters

My father wants to check 1. Given the function f (x) = x ^ 3-ax ^ 2 + BX (a, B are constants), we can get the extremum at x = - 1 and x = 3. (1) find the value of a, B; (2) find the monotone increasing interval of F (x). (2) let the lengths of three sides of △ ABC be a, B, C, a = 3, C = 2, B = 120 degrees respectively. (1) find the length of side B; (2) find the area of △ ABC. (3) known proposition P: x ^ 2-2x-3

I hope to add your Q and teach you these problems and math slowly
And your values
Have you had your winter vacation?
If you think it's OK, choose me