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Misha Larkins [42]
3 years ago
8

Show cos 20 * cos 40 * cos 80 =1/8

Mathematics
1 answer:
Delicious77 [7]3 years ago
8 0
 cos 20 cos 40 cos 80 = 
= ( 2 sin 20 cos 20 cos 40 cos 80 ) / 2 sin 20 =
( multiple and divide by 2 sin 20 )
= ( sin 40 cos 40 cos 80 ) / 2 sin 20 =
= ( 1/2 sin 80 cos 80 ) / 2 sin 20 = 
= ( sin 80 cos 80 ) / 4 sin 20 = 
= 1/2 sin 160 / 4 sin 20 = 
= sin 160 / 8 sin 20 =  ( and since:  sin 160 = sin 20 )
= 1 / 8 
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Kate sold 12 of her paintings and purchased 7 more. if kate has 21 paintings now, how many paintings did she have to begin with?
kicyunya [14]
First, let x or any variable represent the number of paintings Kate initially has. After selling 12 of it, her paintings now becomes only x - 12. Then, she purchased 7 more making the number of her paintings become x - 12 + 7 = x - 5. This number tantamount to 21. 

                                           x - 5 = 21      ; x = 26

Thus, Kate initially had 26 paintings. 
7 0
3 years ago
Si consideras como base uno de los rectángulos de dimensiones de 5cm y 3cm ¿cuanto mide la altura de ese prisma?
Vinvika [58]

Respuesta:

h = V / 15

Explicación paso a paso:

El volumen de un prisma rectangular se calcula usando la relación:

Largo ancho alto

Donde, largo y ancho son la dimensión de la base

Por eso,

Volumen = Base * altura

Volumen = (5 cm * 3 cm) * altura

De la pregunta, no se da el volumen, por lo tanto, tomamos el volumen como V en otro para calcular la altura, h

V = 15h

Divide ambos lados entre 15

V / 15 = 15h / 15

V / 15 = h

5 0
3 years ago
A) Work out the value of 5^2 – 1^5× 2^4<br>b) Work out the value of 7^2 + 4^3 ÷ 2^5​
NemiM [27]
First you have to know BODMAS/BIDMAS (idk if all schools teach it like this) but this is the order in which you complete questions so it’s Brackets, Indices, Division/Multiplication, Addition/Subtraction
a) 5^2 is 5x5 which equals 25 1 to the power of anything is always 1 and 2^4 is 2x2x2x2 which is 16
So 5^2-1^5x2^4 = 25-1x16 which is then 25-16 = 9
b) 7^2+4^3 divided by 2^5 so 7^2 is 7x7 which = 49 then 4^3 means 4x4x4 = 64 and 2^5 is 2x2x2x2x2 which equals 32 so
7^2+4^3 divides by 2^5 is 49+64/32 = 49+2 which is 51
8 0
3 years ago
Don’t know how to do this!
hram777 [196]
U+(v-t)
that’s the answer!
8 0
3 years ago
Read 2 more answers
If the suspect is found guilty, then he will go to prison.
Marrrta [24]

Answer:

If the suspect goes to prison, then he was found guilty.

Step-by-step explanation:

Means the same thing. If you guilty, you get the jail time. Same thing as before. The only other one it could be is the first one. But you could argue that one.

4 0
3 years ago
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