2, because a+ 1/a= root number 10.
a2+ 1/a2+2= 10
a2+ 1/a2-2=6
(a- 1/a)2=6
The square root of a- 1/a = 6.
3. The root number four and two thirds is equal to the root number three.
4. Use Pythagorean Theorem
The square of c = the square of (2 radicals 3+ 1)+ the square of (2 radicals 3- 1) =26.
So c= root number 26
5. The square of x+5x-6 =(x+6)(x- 1)
Because x= radical number 5-1.
So x+6= radical number 5+5; X- 1= radical number 5-2
That is, the original formula = (radical number 5+5) (radical number 5-2)= three radical numbers 5-5.
6、 189=3×3×3×7
Because n is a positive integer, the root sign 189n is an integer.
So the minimum value of n is 3×7=2 1.
7. The radius should be1m..
So the total height is 3 times 3+2 of the root number 3 (difficult to draw and explain, please forgive me ~ ~)
8. If the length of the rectangle is x, the width is (0.06/x).
Judging from the meaning of the question:
2(0.06/x+x)= 1
Solution: x=2/ 10 or 3/ 10.
That is, the length of a rectangle is 2/ 10 or 3/ 10, and the width is 5 or 10/3 (the length and width can be reversed).
9,3x (2x+1) = 4x+2 can be changed to
(2x+ 1)(3x-2)=0
Solution: x 1=- 1/2 x2=2/3.
10, let the diagonal lines of the diamond be x and y respectively.
Judging from the meaning of the question:
x+y= 10
xy/2= 12
The solution is x=4 y=6.
Using Pythagorean Theorem:
The side length is the root sign 13.
The circumference is four times of the root number 13.
The correct rate is 100%!
Nothing upstairs is right ~ ~
It's your business to add points or not ~!