Binary quadratic equations & factorization Solving equations x ^ 2 + y ^ 2 = 20 2x^2-3xy-2y^2=0 Factoring factor 2x ^ 2-3x-1 = 0 in real range

Binary quadratic equations & factorization Solving equations x ^ 2 + y ^ 2 = 20 2x^2-3xy-2y^2=0 Factoring factor 2x ^ 2-3x-1 = 0 in real range

The second formula is: (2x + y) (x-2y) = 0, then 2x + y = 0 or x-2y = 0, so y = - 2x or y = x / 2 is substituted into 1 formula respectively, then x ^ 2 + 4x ^ 2 = 20, x = 2 or - 2, then y = - 4 or 4x ^ 2 + x ^ 2 / 4 = 20, then x = 4 or - 4, then y = 2 or - 2, so there are four groups (2, - 4), (- 2,4), (4,2), (- 4, - 4) in real numbers

A system of equations consisting of two bivariate quadratic equations, one of which can be factorized into two bivariate quadratic equations
(1) What is the condition that the system of equations has no real solution?
(2) What are the conditions for this system to have a unique real solution?
(3) What are the conditions for this system to have exactly two real number solutions?
(4) What are the conditions for this system to have exactly three real number solutions?
(5) What are the conditions for this system to have exactly four real number solutions?

Let this equation be reduced to f = GH
(1) If for any x, the discriminant 1 and 2 are less than 0, there is no solution
(2) If for any x, discriminant 1 = 0, discriminant 2 < 0, or discriminant 2 = 0, discriminant 1 < 0 has unique solution
(3) For any x, discriminant 1 = 0, discriminant 2 = 0, or discriminant 1 < 0, discriminant 2 > 0; or discriminant 1 > 0, discriminant 2 < 0
(4) For any x, discriminant 1 = 0, discriminant 2 > 0, or discriminant 1 > 0, discriminant 2 = 0;
(5) For any x, discriminant 1 > 0, discriminant 2 > 0

Given the root of binary quadratic equations, how to find binary quadratic equations
Given that y = 6 when x = 1, y = 3 when x = 2, we can solve the binary quadratic equations

xy=6
3x+y=9
There are countless answers

The concrete solution of binary fraction equation

The main idea is to simplify the two formulas first, and then substitute a simplified equation of X equal to y into the two formulas, so as to solve y, and then substitute the value of Y into the simplified equation of y to solve X
Or we can simplify an equation where y is equal to X and substitute it into formula 2, so that we can solve x, and then we can solve y by substituting the value of X into the simplified equation
Either way

As shown in the figure, point O is a point within △ ABC, and ob bisects ∠ ABC, OC bisects ∠ ACB, ∠ BOC = 130 °, then the degree of ∠ A is______ ．

According to the sum of internal angles of triangle is 180 °∠ 1 + ∠ 3 = 180 ° - 130 ° = 50 °, OB bisects ∠ ABC, OC bisects ∠ ACB, so ∠ ABC + ∠ ACB = 50 °× 2 = 100 °; in △ ABC, ∠ a = 180 ° - 100 ° = 80 °; answer: the degree of ∠ A is 80 °. So the answer is 80 °

19 and 8, 64 and 80, 17 and 102

The greatest common factor of 19 and 8 is 1
64 and 80 greatest common factor 16
Least common multiple 320
17 and 102 greatest common factor 17
Least common multiple 102
If you don't understand this question, you can ask,

Finding the regular determinant of calculating elements
2 a a a a
a 2 a a a
a a 2 a a
a a a 2 a
a a a a 2
also
1+x 1 1 1
1 x+1 1 1
1 1 x+1 1
1 1 1 x+1
and
1+a 1 1 1
2 2+a 2 2
3 3 3+a 3
4 4 4 4+a
The detailed process and thinking of the calculation of the three determinants

These three problems can be calculated in the same way. (of course, there are several different ways to achieve the goal.) let me solve the second and third problems. The first problem is for you to "practice"! 2) C1 = C1 + C2 + C3 + C4d = | 4 + x 11 | 4 + x 1 + x 14 + x 11 + x 14 + x 11 + x = (4 + x) * | 1

12 35 minus the quotient of a number divided by 8, the difference is 380, what is the number

Let X be
12*35-x/8=380
x/8=420-380
x=320

Find the limit of (x-arcsinx) / (SiNx) ^ 3 when x approaches 0

1. This problem is infinitesimal / infinitesimal infinitive; 2. The solutions to this problem are as follows: & nbsp; & nbsp; & nbsp; the first method is to use Roberta's derivative rule; the second method is to use McLaurin series expansion, there are many calculus teachers, there are many calculus teachers, there are many calculus teachers, there are many calculus teachers, there are many calculus teachers, there are many calculus teachers, there are many calculus teachers, there are many calculus teachers, there are many calculus teachers, there are many calculus teachers, there are many calculus teachers, there are many calculus teachers, there are many calculus teachers, there are many calculus teachers

Simple calculation of 12.8 + 0.7 + 5.49

13+1+6-0.2-0.3-0.5-0.01