1. Which of the following is the square of a binomial? O a2 + b2 O 16x2 +9y2 O m2-mn + n2 O c2-2cd+d2

The figure shows two triangles on a coordinate grid:

svet-max [94.6K]

Answer:

Whats up good luck... sorry my answer didnt submit

Step-by-stp explanation:

4 0

2 years ago

Select all point that lie on the circle

Vitek1552 [10]

Answer:

jjjokiioololll.hgyuhhkopohjo

6 0

2 years ago

Please help <br><br> I need the answer

True [87]

Answer:

D. 14448

Step-by-step explanation:

S = Base area + lateral surface area

=2*(1/2*(56*42)) + (56+42+70)*72

= 2352 + 12096

= 14448

3 0

2 years ago

How to know if a function is periodic without graphing it ?

zhenek [66]

A function $f(t)$ is periodic if there is some constant $k$ such that $f(t+k)=f(k)$ for all $t$ in the domain of $f(t)$ . Then $k$ is the "period" of $f(t)$ .

Example:

If $f(x)=\sin x$ , then we have $\sin(x+2\pi)=\sin x\cos2\pi+\cos x\sin2\pi=\sin x$ , and so $\sin x$ is periodic with period $2\pi$ .

It gets a bit more complicated for a function like yours. We're looking for $k$ such that

$\pi\sin\left(\dfrac\pi2(t+k)\right)+1.8\cos\left(\dfrac{7\pi}5(t+k)\right)=\pi\sin\dfrac{\pi t}2+1.8\cos\dfrac{7\pi t}5$

Expanding on the left, you have

$\pi\sin\dfrac{\pi t}2\cos\dfrac{k\pi}2+\pi\cos\dfrac{\pi t}2\sin\dfrac{k\pi}2$

and

$1.8\cos\dfrac{7\pi t}5\cos\dfrac{7k\pi}5-1.8\sin\dfrac{7\pi t}5\sin\dfrac{7k\pi}5$

It follows that the following must be satisfied:

$\begin{cases}\cos\dfrac{k\pi}2=1\\\\\sin\dfrac{k\pi}2=0\\\\\cos\dfrac{7k\pi}5=1\\\\\sin\dfrac{7k\pi}5=0\end{cases}$

The first two equations are satisfied whenever $k\in\{0,\pm4,\pm8,\ldots\}$ , or more generally, when $k=4n$ and $n\in\mathbb Z$ (i.e. any multiple of 4).

The second two are satisfied whenever $k\in\left\{0,\pm\dfrac{10}7,\pm\dfrac{20}7,\ldots\right\}$ , and more generally when $k=\dfrac{10n}7$ with $n\in\mathbb Z$ (any multiple of 10/7).

It then follows that all four equations will be satisfied whenever the two sets above intersect. This happens when $k$ is any common multiple of 4 and 10/7. The least positive one would be 20, which means the period for your function is 20.

Let's verify:

$\sin\left(\dfrac\pi2(t+20)\right)=\sin\dfrac{\pi t}2\underbrace{\cos10\pi}_1+\cos\dfrac{\pi t}2\underbrace{\sin10\pi}_0=\sin\dfrac{\pi t}2$

$\cos\left(\dfrac{7\pi}5(t+20)\right)=\cos\dfrac{7\pi t}5\underbrace{\cos28\pi}_1-\sin\dfrac{7\pi t}5\underbrace{\sin28\pi}_0=\cos\dfrac{7\pi t}5$

More generally, it can be shown that

$f(t)=\displaystyle\sum_{i=1}^n(a_i\sin(b_it)+c_i\cos(d_it))$

is periodic with period $\mbox{lcm}(b_1,\ldots,b_n,d_1,\ldots,d_n)$ .

4 0

2 years ago

Hakim saves money for one year to buy a computer.

elena55 [62]

Answer:

$111

Step-by-step explanation:

First we need to take a look at the bank account of Hakim. Hakim initially invested $700 in the bank with a 5% simple interest annually. Since Hakim waited for an entire year before buying the computer, he will then have the extra 5% interest from the bank.

Let's first compute for how much Hakim will have in total in the bank.

A = P(1 + rt)

P = 700 Initial Investment

r = 5% or 0.05 Interest

t = 1 Year

A = 700(1 + (0.05 x 1))

A = 700(1 + 0.05)

A = 700(1.05)

A = 735

So now we know that Hakim has a total of $735 in his bank account.

Now let's move on to calculating the total cost of the computer. We know that the sales tax is always computed after the discounted price.

So first we find the discounted price.

x = 750

d = 20% or 0.20

Discount = 750 x 0.20

Discount = 150

Now that we have the discount of the computer, we then simply subtract the discount to the initial price.

750 - 150 = 600.

The computer will then cost $600 with the discounted price.

Now we have to find the sales tax.

Sales Tax = 4% or 0.04

Total Discounted Price = 600

600 x 0.04 = $24

Now that we have the sales tax, we simply add the sales tax to the discounted price.

600 + 24 = 624.

Now that we know how much the total cost of the computer is with the discount and sales tax, we simply subtract the total cost of the computer to Hakim's current account balance.

735 - 624 = 111

Hakim will have a total of $111 in his bank account after purchasing the computer.

4 0

3 years ago

1. Which of the following is the square of a binomial? O a2 + b2 O 16x2 +9y2 O m2-mn + n2 O c2-2cd+d2​

1. Which of the following is the square of a binomial? O a2 + b2 O 16x2 +9y2 O m2-mn + n2 O c2-2cd+d2