All categories

2 years ago

Please help urgently extra points and mark brainlist

Mathematics

1 answer:

Sergeeva-Olga [200]2 years ago

3 0

Answer:

B. -3.5 and +3.5

Step-by-step explanation:

You might be interested in

[tex]cos {}^{4} α+sin {}^{4} α= \frac{1}{4} (3+cos4α)<br>Prove:<br>

asambeis [7]

Given:

$\cos^4 \alpha+\sin^4\alpha=\dfrac{1}{4}(3+\cos 4 \alpha)$

To prove:

The given statement.

Proof:

We have,

$\cos^4 \alpha+\sin^4\alpha=\dfrac{1}{4}(3+\cos 4 \alpha)$

$LHS=\cos^4 \alpha+\sin^4\alpha$

$LHS=(\cos^2 \alpha)^2+(\sin^2 \alpha)^2$

$LHS=(\cos^2 \alpha+\sin^2\alpha)^2-2\sin ^2\alpha\cos^2 \alpha$ $[\because a^2+b^2=(a+b)^2-2ab]$

$LHS=(1)^2-2(1-\cos^2 \alpha)\cos^2 \alpha$ $[\because \cos^2 \alpha+\sin^2\alpha=1]$

$LHS=1-2\cos^2 \alpha+2\cos^4 \alpha$

Now,

$RHS=\dfrac{1}{4}(3+\cos 4 \alpha)$

$RHS=\dfrac{1}{4}[3+(2\cos^2 2\alpha-1)]$ $[\because \cos 2\theta=2\cos^2\theta -1]$

$RHS=\dfrac{1}{4}[2+2\cos^2 2\alpha]$

$RHS=\dfrac{1}{4}[2+2(2\cos^2 \alpha-1)^2]$ $[\because \cos 2\theta=2\cos^2\theta -1]$

$RHS=\dfrac{1}{4}[2+2(4\cos^4 \alpha-4\cos \alpha+1)]$ $[\because (a-b)^2=a^2-2ab+b^2]$

$RHS=\dfrac{1}{4}[2+8\cos^4 \alpha-8\cos \alpha+2]$

$RHS=\dfrac{1}{4}[4+8\cos^4 \alpha-8\cos \alpha]$

$RHS=1+2\cos^4 \alpha-2\cos \alpha$

$RHS=1-2\cos^2 \alpha+2\cos^4 \alpha$

$LHS=RHS$

Hence proved.

8 0

3 years ago

Use the distributive property two different ways to find the product of 127 and 32

cricket20 [7]

127 = 100 +27
32 = 30 +2
so 127 x 32 = (100 + 27) x (30+2) = (100x30) + (100x2) + (27x30) +(27x2)
= 3000+200+810+54 = 4064

second way:

127 = 100 + 27
127 x 32 = (100+27) x 32 = (100x 32) + ( 27x32) = 3200 + 864 = 4064

5 0

3 years ago

George drives at 45mi/h. write two expressions for the number of miles George travels in h hours

GaryK [48]

45h=miles in h hours

7 0

3 years ago

Read 2 more answers

If thewronskian w of f and g is 3e4t,and if f(t) = e2t,find g(t).

ehidna [41]

$W(f(x),g(x))=\begin{vmatrix}f(x)&g(x)\\f'(x)&g'(x)\end{vmatrix}=f(x)g'(x)-g(x)f'(x)$

We have $f(t)=e^{2t}\implies f'(t)=2e^{2t}$ , so

$W(f(t),g(t))=e^{2t}g'(t)-2e^{2t}g(t)=3e^{4t}$
$\implies e^{-2t}g'(t)-2e^{-2t}g(t)=3$
$\implies\dfrac{\mathrm d}{\mathrm dt}[e^{-2t}g(t)]=3$
$\implies e^{-2t}g(t)=\displaystyle\int3\,\mathrm dt$
$\implies e^{-2t}g(t)=3t+C$
$\implies g(t)=3te^{2t}+Ce^{2t}$

where $C$ is any arbitrary constant.

8 0

3 years ago

Mike spent half of his allowance going to the movies.He washed the family car and earned 9 dollars.What is his weekly allowance

Bezzdna [24]

Answer:

Step-by-step explanation:

If he spends half his money then washes the family car and he ends up with 18 dollars that means he spent 9 witch is half of 18 and he adds 9 more dollars which is why his allowance is 18 dollars

7 0

3 years ago