A car company wants to reduce the use of the gas fuleled cars

Please help meee, I’m having trouble in math. I solved the answer but got none of these.

tino4ka555 [31]

The answer is C

2.5 + 3.4 = 5.9

So:

5.9 x 10^4

6 0

3 years ago

Prove that sinxtanx=1/cosx - cosx

maks197457 [2]

Answer:

See below

Step-by-step explanation:

We want to prove that

$\sin(x)\tan(x) = \dfrac{1}{\cos(x)} - \cos(x), \forall x \in\mathbb{R}$

Taking the RHS, note

$\dfrac{1}{\cos(x)} - \cos(x) = \dfrac{1}{\cos(x)} - \dfrac{\cos(x) \cos(x)}{\cos(x)} = \dfrac{1-\cos^2(x)}{\cos(x)}$

Remember that

$\sin^2(x) + \cos^2(x) =1 \implies 1- \cos^2(x) =\sin^2(x)$

Therefore,

$\dfrac{1-\cos^2(x)}{\cos(x)} = \dfrac{\sin^2(x)}{\cos(x)} = \dfrac{\sin(x)\sin(x)}{\cos(x)}$

Once

$\dfrac{\sin(x)}{\cos(x)} = \tan(x)$

Then,

$\dfrac{\sin(x)\sin(x)}{\cos(x)} = \sin(x)\tan(x)$

Hence, it is proved

5 0

3 years ago

Prove that for any natural n the number 3^(n+4)−3^n is divisible by 16.

gtnhenbr [62]

Answer:

Proved (See Explanation)

Step-by-step explanation:

Show that 3ⁿ⁺⁴ - 3ⁿ is divisible by 16.

This is done as follows

$\frac{3^{n+4} - 3^n}{16}$

From laws of indices;

aᵐ⁺ⁿ = aᵐ * aⁿ.

So, 3ⁿ⁺⁴ can be written as 3ⁿ * 3⁴.

$\frac{3^{n+4} - 3^n}{16}$ becomes

$\frac{3^n * 3^4 - 3^n}{16}$

Factorize

$\frac{3^n(3^4 - 1)}{16}$

$\frac{3^n(81 - 1)}{16}$

$\frac{3^n(80)}{16}$

3ⁿ * 5

5(3ⁿ)

<em>The expression can not be further simplified.</em>

<em>However, we can conclude that when 3ⁿ⁺⁴ - 3ⁿ is divisible by 16, because 5(3ⁿ) is a natural whole number as long as n is a natural whole number.</em>

3 0

3 years ago

Can someone help me?

Pani-rosa [81]

Answer: m=−3

Step-by-step explanation: −40−2(3m+1/2)=7m−2

−40+(−2)(3m)+(−2)(1/2)=7m+−2

−40+−6m+−1=7m+−2

(−6m)+(−40+−1)=7m−2

−6m+−41=7m−2

−6m−41−7m=7m−2−7m

−13m−41+41=−2+41

−13m/−13=39/−13

m=−3

What mistake I guess Keith did make is he subtracted 2 from -39 which equaled to -37 which caused him divide -37 by 13 when it should have been 39 divided by 13 because he should have left 39 alone and not have subtracted 2 from it also it should not have been negative basically what I'm trying to say is that he did his division and subtraction wrong.