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2 years ago

Trigonometric identities Simplify cos^2 theta -1/ 4 sin^2 theta

Mathematics

1 answer:

Veronika [31]2 years ago

4 0

Answer:

Step-by-step explanation:

using the identity

sin²x + cos²x = 1 ( subtract 1 from both sides )

sin²x + cos²x - 1 = 0 ( subtract sin²x from both sides )

cos²x - 1 = - sin²x

then

$\frac{cos^20-1}{4sin^20}$

= $\frac{-sin^20}{4sin^20}$ ← cancel sin²Θ on numerator and denominator

= $\frac{-1}{4}$

= - $\frac{1}{4}$

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3 years ago

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What’s the correct answer for this ?

Ann [662]

Answer:

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2 years ago

Can someone please help me I really need help please help me

scZoUnD [109]

Answer:

18.87 square cm.

Step-by-step explanation:

The area of the rectangle will be (4 + 4) * 4, since the length of the rectangle would be the diameter of the circle, and the width of the rectangle would be the radius. (4 + 4) * 4 = 8 * 4 = 32 square cm.

Then, we can calculate the area of the semicircle. The area of a circle is pi * r^2, so the area of a semicircle will be half of that. pi * (4^2) / 2 = pi * 16 / 2 = 8pi. 8 * 3.14159265 = 25.1327412 square cm.

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harina [27]

Answer:

The correct option is (B).

Step-by-step explanation:

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The mean of a data set is:

$\bar X=\frac{1}{n}\sum\limits^{n}_{x=0}{X}$

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So, the mean and median weight for the 3 kittens lies in the middle of this range.

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