Cos(A-B) = cosAcosB + sinAsinB
<span>
cos(</span>π/2 - θ) = cos(π/2)cosθ + sin(π/2)sinθ
π/2 = 90°
cos(π/2) = cos90° = 0. sin(π/2) = sin90° = 1
cos(π/2 - θ) = cos(π/2)cosθ + sin(π/2)sin<span>θ
</span>
= 0*cosθ + 1*sin<span>θ = </span>sin<span>θ
Therefore </span>cos(π/2 - θ) = sin<span>θ
QED </span>
(a) From the histogram, you can see that there are 2 students with scores between 50 and 60; 3 between 60 and 70; 7 between 70 and 80; 9 between 80 and 90; and 1 between 90 and 100. So there are a total of 2 + 3 + 7 + 9 + 1 = 22 students.
(b) This is entirely up to whoever constructed the histogram to begin with... It's ambiguous as to which of the groups contains students with a score of exactly 60 - are they placed in the 50-60 group, or in the 60-70 group?
On the other hand, if a student gets a score of 100, then they would certainly be put in the 90-100 group. So for the sake of consistency, you should probably assume that the groups are assigned as follows:
50 ≤ score ≤ 60 ==> 50-60
60 < score ≤ 70 ==> 60-70
70 < score ≤ 80 ==> 70-80
80 < score ≤ 90 ==> 80-90
90 < score ≤ 100 ==> 90-100
Then a student who scored a 60 should be added to the 50-60 category.
The value of ac is 36 and the value of b is 13. Then the value of ac + b is 49. The two numbers are 4 and 9.
<h3>What is polynomial?</h3>
Polynomial is an algebraic expression that consists of variables and coefficients. Variable are called unknown. We can apply arithmetic operations such as addition, subtraction, etc. But not divisible by variable.
Consider the trinomial 6x² + 13x + 6.
Compare with the standard equation, we have
ax² + bx + c
Then we have
a = 6
b = 13
c = 6
The product of ac will be
ac = 6 × 6 = 36
The sum of ac and b will be
ac + b = 36 + 13 = 49
The two numbers that have a product of ac and a sum of b are 4 and 9.
More about the polynomial link is given below.
brainly.com/question/17822016
Answer:
The answer is 6
Step-by-step explanation:
42 divided by 7=6
Answer:
The second table.
Step-by-step explanation:
In the first table, the speed goes from 45 down to 43; then down to 41; then up to 42; then up to 43. It decreases and then increases. This is not the correct table.
In the second table, the speed goes from 45 up to 47; then up to 49; then down to 48; then down to 47. It increases and then decreases; this is the correct table.
To verify, we check the last two tables. The third table stays at 45, then decreases to 43 and 41. This is not correct.
The last table decreases from 45 to 43, then decreases to 41, then stays constant. This is not correct.
The second table is the only correct one.
