Answer:
Step-by-step explanation:
7). (x + 3)(x + 7)
= x(x + 7) + 3(x + 7)
= x² + 7x + 3x + 21
= x² + 10x + 21
8). (4x + 2)(x - 2)
= 4x(x - 2) + 2(x - 2)
= 4x² - 8x + 2x - 4
= 4x² - 6x - 4
9). (3x + 2)(2x + 5)
= 3x(2x + 5) + 2(2x + 5)
= 6x² + 15x + 4x + 10
= 6x² + 19x + 10
10). (x² - 6)(x - 4)
= x²(x - 4) - 6(x - 4)
= x³ - 4x² - 6x + 24
11). (x² + 9)(x - 3)
= x²(x - 3) + 9(x - 3)
= x³ - 3x² + 9x - 27
12). (4x²- 4)(2x + 1)
= 4x²(2x + 1) - 4(2x + 1)
= 8x³ + 4x² - 8x - 4
Answer:
Option D (4, -5)
Step-by-step explanation:
This question can be solved by various methods. I will be using the hit and trial method. I will plug in all the options in the both the given equations and see if they balance simultaneously.
Checking Option 1 by plugging (-4, -5) in the first equation:
-2(-4) + 6(-5) = -38 implies 8 - 30 = -38 (not true).
Checking Option 2 by plugging (-5, 4) in the first equation:
-2(-5) + 6(4) = -38 implies 10 + 24 = -38 (not true).
Checking Option 3 by plugging (1, -6) in the second equation:
3(1) - 4(-6) = 32 implies 3 + 24 = 32 (not true).
Since all the options except Option 4 have been ruled out, therefore, (4,-5) is the correct answer!!!
Step-by-step explanation:
First
since its follow the pattern Intercept Max... Intercept Min...
Its a positive sine graph
Asin(B(x-0))<0.25
A=1
B=2π/period
period From the graph = 2π
B=2π/2π
B=1
Sin(x)<0.25
I'd go with C.
Question 21
Let's complete the square
y = 3x^2 + 6x + 5
y-5 = 3x^2 + 6x
y - 5 = 3(x^2 + 2x)
y - 5 = 3(x^2 + 2x + 1 - 1)
y - 5 = 3(x^2+2x+1) - 3
y - 5 = 3(x+1)^2 - 3
y = 3(x+1)^2 - 3 + 5
y = 3(x+1)^2 + 2
Answer: Choice D
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Question 22
Through trial and error you should find that choice D is the answer
Basically you plug in each of the given answer choices and see which results in a true statement.
For instance, with choice A we have
y < -4(x+1)^2 - 3
-7 < -4(0+1)^2 - 3
-7 < -7
which is false, so we eliminate choice A
Choice D is the answer because
y < -4(x+1)^2 - 3
-9 < -4(-2+1)^2 - 3
-9 < -7
which is true since -9 is to the left of -7 on the number line.
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Question 25
Answer: Choice B
Explanation:
The quantity (x-4)^2 is always positive regardless of what you pick for x. This is because we are squaring the (x-4). Squaring a negative leads to a positive. Eg: (-4)^2 = 16
Adding on a positive to (x-4)^2 makes the result even more positive. Therefore (x-4)^2 + 1 > 0 is true for any real number x.
Visually this means all solutions of y > (x-4)^2 + 1 reside in quadrants 1 and 2, which are above the x axis.
I think the answer is (-2,2)
