12 out of 11 × () equals 4 out of 9 × () equals 1

12 out of 11 × () equals 4 out of 9 × () equals 1

There are at least two possibilities: 12 out of 11 × (11 out of 12) equals 4 out of 9 × (9 out of 4) equals 1
Or [12 × (12 / 11)] of 11 is equal to [4 / 9)] of 9 is equal to 1

It is known that SiNx cosx = 1 / 5, X is an acute angle and the value of SiNx + cosx

Since SiNx cosx = 1 / 5 > 0 and X is an acute angle, Π / 4

A simple method of 12 × 98 + 24 × 4-36 × 2

A simple method of 12 × 98 + 24 × 4-36 × 2
12×98+24×4-36×2
=12×98+12×2×4-12×3×2
=12×（98+2×4-3×2）
=12×（98+8-6）
=12×100
=1200
This problem mainly uses the law of distribution of multiplication for simple calculation

Find the linear equation intersecting with the square / 4 of ellipse x + the square / 9 of ellipse y at two points a and B, and the line segment AB is m (1,1)

Let a x 1 y 1 B x 2 y 2 be substituted into two equations. If we want to reduce x 1 + x 2 = 2, Y 1 + y 2 = 2, the division is k = - 9 / 4 and pass (1,1)

Because 3.2 △ 0.8 = 4, 3.2 is a multiple of 0.8______ (judge right or wrong)

3.2 and 0.8 are decimals, and multiples are relative to integers

The equation 4 ^ + A * 2 ^ x + A + 1 about X has a real number solution. The range of value of a can be obtained by solving it

Let y = 2 ^ x > 0, and the equation is as follows:
Y ^ 2 + ay + A + 1 = 0 must have at least one positive root
When delta = a ^ 2-4 (a + 1) = a ^ 2-4a-4 > = 0 --- > a > = 2 + 2 √ 2 or a = 2 + 2 √ 2, Y1 + y2 = - A0 is two same sign, and the sum is negative, so it is two negative roots
When A0, the sum of two is positive, then there is at least one positive root
So the range of real number solution is: a

Dividing a fraction by 3 is equal to expanding the fraction a to three times the original B, reducing it by three times C, reducing it to one third of the original D, and increasing it by three times
Which one

A fraction divided by 3 is equal to the fraction [C, reduce to 1 / 3 of the original]
For example: 8 / 3 = 8 × 1 / 3 = 8 / 3

If 3x = 2Y, then 6x to the second power + 11xy-10y to the second power

Because 3x = 2Y, (use y to express x), x = 2 / 3Y brings x = 2 / 3Y into 6x ^ 2 + 11xy-10y ^ 2, (6x ^ 2 is the quadratic power of 6x, 10Y ^ 2 is the quadratic power of 10Y) 6 * (2 / 3Y) ^ 2 + 11 * (2 / 3Y) * y-10y ^ 2 = 6 * (4 / 9 * y ^ 2) + 22 / 3 * y ^ 2-10y ^ 2 = 8 / 3 * y ^ 2 + 22 / 3 * y ^ 2-10y ^ 2 = 30 / 3Y ^ 2-10y ^ 2 = 10Y ^

Among the numbers 40, 12, 37, 39, 45, 18, 10, 26, 91, 69, 234, 76 and 600, the odd number is: U_ Even numbers are:___ .
The multiple of 3 has (), the factor of 5 has (), the prime number has (), and the total number has ()

The odd numbers are:_ 37,39,45,69,91_ The even numbers are: 40,12,18,10,26_ 234,76,600__ .
The multiple of 3 is (12,39,15,18,69234600), the factor of 5 is (40,45,10600), the prime number is (37,), and the total number is (40,12,39,451810,26,91,69234,76600)

If 2x + 5y-3 = 0,4 ^ X-1 * 32 ^ y

2x+5y=3
So the original formula is 4 ^ x △ 4 * 32 ^ y
=2^2x÷4*2^5y
=2^(2x+5y)÷4
=2³÷4
=2