Arrays are useful models for multiplication which can be used in a variety of ways, ranging from highly structured lessons to games and open investigations. An array is formed by arranging a set of objects into rows and columns. Each column must contain the same number of objects as the other columns, and each row must have the same number as the other rows.
The following array, consisting of four columns and three rows, could be used to represent the number sentence 3 x 4 = 12.
I’m having trouble understanding this question.?
X=3 and y=x^2 intersect at (3,9), so your bounds are y=4 and y=9 and and . , so you use the disk method therefore you have to switch variables (even though x^2 is not invertible, because you only need the right side you can use y^(1/2)) so pi*integral( 3^2- (y^(1/2))^2 dy) making it pi*[9y-(1/2)y^2]|y=(4,9) , pi*[25/2]
Question:
Solve the inequality:
5.1 – r ≥ 5
Answer:
r ≤ 0.1
Solution:
Step 1: Given inequality:
5.1 – r ≥ 5
Step 2: Subtract 5.1 from both sides of the inequality
⇒ 5.1 – r – 5.1 ≥ 5 – 5.1
⇒ – r ≥ – 0.1
Step 3: To reverse the inequality, multiply both sides by –1.
⇒ (–r) × (–1) ≥ – 0.1 × (–1)
Negative × Negative = Positive
⇒ r ≤ 0.1
Hence the solution to the given inequality is r ≤ 0.1.
