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1 year ago

Sin70° sin130° sin170°=1/8

1 answer:

7 0

Sin 10° Sin 50° sin 70° = 1/8
Now we multiply upper & bottom both side 2/2

then

➡ 1/2 (2sin 10° sin50° 70°)

➡ 1/2 sin10°( 2sin70° sin50°)

we know that
2 sinA sinB = cos (A-B) - cos (A+B)

Then

➡ 1/2 sin 10° ( cos 20° - cos 120°)

➡ 1/2 sin 10° ( cos 20° - cos (90°+30°))

➡ 1/2 sin 10° ( cos 20° +1/2)

➡ 1/2 sin 10° cos 20° +1/4 sin 10°

again we multiply both upper & bottom side 2/2 so

➡ 1/4 ( 2 sin 10° cos 20°). + 1/4 sin 10°

we know that
2 sinA cos B = sin (A+B) - sin (A- B)

➡ 1/4 (sin 30° - sin 10°) + 1/4 sin 10°

➡ 1/4 sin 30° - 1/4 sin 10° + 1/4 sin 10°

we know sin 30° = 1/2

➡ 1/4 × 1/2

➡ = 1/8 hence proved

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According to the manufacturer, about 26% of sour candy in a package of Sandy's Sours are grape. What is the probability that the

Leto [7]

Answer:

Step-by-step explanation:

We assume that there are 100 sour candies, Thus-

26 % of candy are grape implies that 26% of 100 candies are grape that is equal to 26

Now remaing candies that are not grape are 100-26 = 74

Based on the rule of multiplication:

P(A ∩ B) = P(A)/ P(B|A)

 In the beginning, there are 26grape candies, probability of choosing first grape candy = 26C1 = 26

 After the first selection, we replace the selected grape candy so there are still 100 candies in the bag P(B|A) = 100C3 = 100 x 99 x 98 x 97!/3! X 97!

= 50 x 33 x 98

So probability =1/ 50 x 33 x 98 x 26

= 1/4204200

8 0

2 years ago

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The value of good wine increases with age. Thus, if you are a wine dealer, you have the problem of deciding whether to sell your

Katyanochek1 [597]

Answer: 64 years

Step-by-step explanation:

Let assume the dealer sold the bottle now for $P, then invested that money at 5% interest. The return would be:

R1 = P(1.05)^t,

This means that after t years, the dealer would have the total amount of:

$P×1.05^t.

If the dealer prefer to wait for t years from now to sell the bottle of wine, then he will get the return of:

R2 = $P(1 + 20).

The value of t which will make both returns equal, will be;

R1 = R2.

P×1.05^t = P(1+20)

P will cancel out

1.05^t = 21

Log both sides

Log1.05^t = Log21

tLog1.05 = Log21

t = Log21/Log1.05

t = 64 years

The best time to sell the wine is therefore 64years from now.

7 0

2 years ago

Sofia ordered sushi for a company meeting. They change plans and increase how many people will be at the meeting, so they need a

saveliy_v [14]

Answer:

Sofia will order 7 more rolls of sushi (84 pieces) and pay $56

Step-by-step explanation:

They need at least 100 pieces of sushi

Sofia had ordered and paid for 24 pieces of sushi already

Sushi comes in rolls

Each roll=12 pieces at $8

R=additional rolls that Sofia orders

Additional sushi= Needed sushi - ordered sushi

=100-24

=76 pieces of sushi

Each roll has 12 pieces

76/12=6.33

Sofia has to order in rolls

So, she will order 7 more rolls of sushi of 12 pieces each

12*7=84 pieces

Recall, that they needed at least 100 pieces, so the number of pieces could be more than 100

If Sofia orders 84 pieces + the already ordered 24 pieces

Total pieces=108 pieces

She has paid for 24 pieces (3 rolls) at $8 per roll

7 rolls=$8*7

=$56

7 0

2 years ago

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Which expression has the same GCF as 15x2 - 21x?

Mice21 [21]

Answer:

$15x^2 +21 x$

Step-by-step explanation:

We have the following expression:

$15x^2 -21 x$

We can find the GCF with the following steps.

1. Find the GCF for the numerical part 15 and -21

The factors for 15 are : 1,3,5,15

The factors for -21 are -21,-7,-3,-1,1,3,7,21

And the common factors are 1,3

The GCF for the numerical part is 3*1 = 3

2. Find the GCF for the variable

The factors of x^2 are : x*x

The factors of x are: x

The common factors are x for this case, so then the GCF for the variable part is x

3. Multiply the two results from steps 1 and 2

GCf= 3*x = 3x

If we consider the new expression:

$15x^2 +21x$

We can find the GCF with the following steps.

1. Find the GCF for the numerical part 15 and -21

The factors for 15 are : 1,3,5,15

The factors for -21 are 1,3,7,21

And the common factors are 1,3

The GCF for the numerical part is 3*1 = 3

2. Find the GCF for the variable

The factors of x^2 are : x*x

The factors of x are: x

The common factors are x for this case, so then the GCF for the variable part is x

3. Multiply the two results from steps 1 and 2

GCf= 3*x = 3x

And as we can see both GCF are equal. So then we satisfy the condition required.

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2 years ago

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At the start of the week, Monique’s savings account had a balance of $326. She made a $45 withdrawal each day for seven days. Du

sammy [17]

Answer:

Step-by-step explanation:

45 times 7= 315

326-315=11

125 times 2=250

250+11=261

so the answer is C. $261

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2 years ago

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Sin70° sin130° sin170°=1/8​

Sin70° sin130° sin170°=1/8