If 3a2-a-2 = 0, then 5 + 2a-6a2=______ ．

If 3a2-a-2 = 0, then 5 + 2a-6a2=______ ．

Therefore, the answer is: 1

Solve the equations 1. X + 1 / 3 = 5x-y / 5, 7Y = 5x + 25 (x = 2, y = 5) 2. 2x-y / 5 = x + Y / 3 = 3 (x = 8, y = 1)

1. (x + 1) / 3 = (5x-y) / 5 simplify both sides by 15 to get 5x + 5 = 15x-3y, then simplify to get 3Y + 5 = 10x (1) formula 7Y = 5x + 25 (2) formula (2) multiply both sides by 2 to get 11y-5 = 50, then get y = 5, substitute (1) formula to get 3 * 5 + 5 = 10x, then get x = 22. (2x-y) / 5 = (x + y)

Excuse me, (3) 80 + x > 3x

80+x>3x
transposition
80>3x-x
80>2x
That is 2x

How to calculate determinant
1 1 1 1
1 2 3 4
1 3 6 10
1 4 10 20

Add - 1 times of line 1 to lines 2, 3, 4:
1 1 1 1
0 1 2 3
0 2 5 9
0 3 9 19
Add - 2, - 3 times of line 2 to lines 3 and 4
1 1 1 1
0 1 2 3
0 0 1 3
0 0 3 10
Add - 3 times of line 3 to line 4:
1 1 1 1
0 1 2 3
0 0 1 3
0 0 0 1
The value of determinant = 1

Is there a simple algorithm for dividing 5 / 4 by {(1 / 5 + 1 / 3) X3 / 2}?

5/4÷【（1/5+1/3）X3/2】
=5/4÷【1/5×3/2+1/3×3/2】
=5/4÷【3/10+1/2】
=5/4÷4/5
=25/16

The process of finding the limit of X → + ∞, X (√ (x ^ 2 + 1) - x)

limx(√(x^2+1)－x)
=limx((x^2+1)－x^2) / (√(x^2+1)+x)
=limx / (√(x^2+1)+x)=1/2

Simple calculation of 4 / 15 △ (13 / 9-2 / 3 × 5 / 6)

4/15÷（13/9-2/3×5/6）=4/15÷（13/9-5/9)=4/15÷8/9=4/15*9/8=3/10

Factorization a ^ 2 [A-B] + 2Ab [A-B] + B ^ 2 [A-B]

The original formula = (a-b) (A & # 178; + 2Ab + B & # 178;)
=(a-b)(a+b)²
Analysis: decomposition factor, there is a common factor to mention the common factor
May I help you!

Known: a = 19911991 Q: what is the remainder of a divided by 13?

In pencil:
1991 / 13 remainder 2
21991 / 13 remainder 8
81991 / 13 remainder 0
That is to say, 199119911991 divided by 13 can be divisible
The remainder of 1991 / 3 is 2
So the remainder of a / 13 = 19911991 / 13, = 8

Given that the line L passes through the point P (1,1) and the inclination angle α = π / 6, the parameter equation of the line L is written
It is known that the straight line L passes through the point P (1,1), and the inclination angle α = π / 6,
(1) Write out the parameter equation of line L
(2) Let L and circle X & sup2; + Y & sup2; = 4 intersect two points a and B, and find the product of the distances from point P to two points a and B

(1) Parameter equation: x = 1 + T √ 3 / 2
y=1+t/2
(t is the parameter)
（2）PA*PB=（2+√2）*（2-√2）=2