Given the | y | of 3 times root x + 5 times, we can find the value range of M = 2 times root x-3 | y | I can't play root. How can I play root

Given the | y | of 3 times root x + 5 times, we can find the value range of M = 2 times root x-3 | y | I can't play root. How can I play root

It is known that 3 √ x + 5 | y | = 7,
The results are as follows: | y | = (1 / 5) (7-3 √ x) ≥ 0,
It can be concluded that: √ x ≤ 7 / 3;
Because M = 2 √ x-3 | y | = 2 √ X - (3 / 5) (7-3 √ x) = (1 / 5) (19 √ x-21), where 0 ≤ √ x ≤ 7 / 3,
Therefore, - 21 / 5 ≤ m ≤ 14 / 3
[use Sogou Pinyin input method to type the Pinyin Dui of "right" and choose 5 to get √, which is used to represent the root sign]

What is the number of real roots of the equation 2 ^ x + a-lgx = O (a > = 0) of X（

0
Draw 2 ^ X and lgx curves
We can clearly see that 2 ^ x > lgx always holds
And a > = 0, which is equivalent to moving 2 ^ X image up a unit,
SO 2 ^ x + a-lgx is always greater than 0

Find the unknowns x.2.75-5x = 2710223: x = 910:0.6 & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; (X-7) △ 5 = 14

（1）2.75-5X+5X=2710+5X              2.75=2710+5X          2.75-2.7=2710+5X-2.7 ...

Mathematics simple operation detailed explanation, do a good job to give 100 points
1>19.2*135-144/1000*1920+209*123/125
1/1*3+1/3*5+1/5*7+.+1/97*99
1/8128+1/254+1/508+1/1016+1/2032+1/4046+1/8128`
44/45*37-8/45
3/4*17+0.25*29
12/13/(53.9*2/3)
2.6/[(7/12-5/16)*1.6]

19.2*135-144/1000*1920+209*123/125 =19.2*135-14.4*19.2+209*(1-2/125)=19.2*(135-14.4)+209-418/125=(20-0.8)*120.6+209-418*8/1000=2412-96.48+209-3.344=2621-99.824=2521.1761/1*3+1/3*5+1/5*7+.+1/97*99=[(1-...

In {an}, Sn = 3 (1-qn) / 2 and a1 + q = 3, we find the values of A4 and S4

Because Sn = A1 * (1-Q ^ n) / (1-Q) = 3 (1-Q ^ n) / 2, so A1 / (1-Q) = 3 / 2, so A1 = 3 (1-Q) / 2 and a1 + q = 3, so 3 (1-Q) / 2 + q = 3 / 2-Q / 2 = 3, so q = - 3, so A1 = 3-q = 6, so A4 = A1 * q ^ 3 = 6 * (- 3) ^ 3 = - 162s4 = A1 * (1-Q ^ n) / (1-Q) = 6 * (1 - (- 3) ^ n) / (1 - (- 3)) = 3 [1 - (- 3) ^ n] / 2

Simple calculation of 98 times 64

98×64
=(100-2)×64
=100×64-2×64
=6400-128
=6272

As shown in the figure, in the isosceles trapezoid ABCD, ad ∥ BC, ab = CD, diagonal AC ⊥ BD, ad = 4cm, BC = 10cm, calculate the area of the trapezoid ABCD

In ABCD, ab = CD, ∧ de = AC = BD, ∧ AC ⊥ BC, F. ∵ ad ∥ CB, de ∥ AC, ∧ quadrilateral, Adec is parallelogram, ∧ de = AC, ad = CE = 4 ∫ isosceles trapezoid. In ABCD, ab = CD, ∧ de = AC = BD, ∧ AC ⊥ BD, CE ∧ ad, ∧ de ⊥ BD, ∧ BDE are isosceles right triangle, and ∫ ad = 4, BC = 10, ∧ DF = 12be = 12 (AD + BC) = 7 cm, the area of the trapezoid is: 1 2 (4 + 10) × 7 = 49

Fill in the operation symbol or bracket in () to make the equation hold
1 in 4 () 1 in 4 () 1 in 4 () 1 in 4 () = 1 in 8.4 () 1 in 4 () 1 in 4 () 1 in 4 () 1 in 4 () 1 in 4 () = 1 in 8

The first question is:
(1/4 × 1/4）÷（1/4 + 1/4）= 1/8
The second topic is:
{ [(1/4)+(1/4)] × （1/4） × （1/4） } ÷ (1/4) = 1/8
or
[ (1/4 - 1/4) + (1/4 + 1/4) ] × 1/4 = 1/8
etc.

Given that the eigenvalues of the third-order matrix A are - 1,1,2, then the eigenvalues of B = a ^ 3-2a ^ 2 are? | B | =?

Let g (x) = x ^ 3 - 2x ^ 2
Because the eigenvalues of a are - 1,1,2
So the eigenvalues of B = g (a) = a ^ 3-2a ^ 2 are g (- 1) = - 3, G (1) = - 1, G (2) = 0,
So | B | = (- 3) * (- 1) * 0 = 0

The sum of the numbers in each digit is 15. How many three digits are there
Why 61? I'll give you a score if I explain it clearly

It's 61,
There are 159 (6), 168 (6), 177 (3), 249 (6), 258 (6), 267 (6), 339 (3), 348 (6), 357 (6), 366 (3), 447 (3), 456 (6), 555 (1)
It adds up to 61, regular