Find the exact value of cos(135 degree + 30 degree)

Answers

Answer 1

Answer: $cos(x+y)=cosxcosy-sinxsiny\nsin(x+y)=sinxcosy+sinycosx\n-------------------------------\ncos(135^o+30^o)=cos135^ocos30^o-sin135^osin30^o=(*)\n----------------------------\ncos135^o=cos(90^o+45^o)=cos90^ocos45^o-sin90^osin45^o\n=0\cdot(\sqrt2)/(2)-1\cdot(\sqrt2)/(2)=-(\sqrt2)/(2)\n\nsin135^o=sin(90^o+45^o)=sin90^ocos45^o+sin45^ocos90^o\n=1\cdot(\sqrt2)/(2)+(\sqrt2)/(2)\cdot0=(\sqrt2)/(2)\n-------------------------------$

$(*)=-(\sqrt2)/(2)\cdot(\sqrt3)/(2)-(\sqrt2)/(2)\cdot(1)/(2)=-(√(6))/(4)-(\sqrt2)/(4)=-(\sqrt6+\sqrt2)/(4)$

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—1(-4)+-2(3)(-4)-(-6-10)

Which term can be added to the list so that the greatest common factor of the three terms is 12h3?36h3, 12h6, __________

6h3

12h2

30h4

48h5

Answers

The term that can be added to the list so the GCF is 12h3 would be 48h5.

The reason being is that 48 is first divisible by 12 and does not yield a fraction, and we can remove upon dividing 3 h's from this term as it contains a total of 5 h's.

The term that can be added to the list so that the greatest common factor of the three terms is 12h3 is D. 48h5

What is a Greatest Common Factor?

This refers to the highest number that can make an exact division of two or three numbers.

Hence, given the terms:

48 is divisible by 12 exactly

If we divide 3 h's, it would also contain a total of 5 h's

Therefore, the answer is 48h5

Read more about the greatest common factor here:

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If EG and HJ are parallel lines and m

Answers

The measure of ∠ JIK is 122°

What are corresponding angles?

Corresponding angles are angles that occur on the same side of the transversal line and are equal in size.

Given that, EG and HJ are parallel lines and m is transversal

∵ ∠ GFI and ∠ JIK are corresponding angles, and corresponding angles between two parallel lines are equal.

∴ m ∠ GFI = m ∠ JIK = 122°

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Answer:

m JIK = 122°

Step-by-step explanation:

HERE, L || M

So, m JIK = m GFI

( since they are corresponding angles pair )

so, m JIK = 122°

6.
Is the line of reflection x, y, or z?

Answers

Answer:

The line of reflection is y.

Step-by-step explanation:

If it was reflection by the x axis, it would of been in the same position, just flipped around.

If it was reflection by the z axis, the two shapes would of been much closer (or further, depends how you look at it) than it is in graph.

Therefore, it is reflected by the y axis. You can also tell since both shapes are equidistant from the y axis.

Hope this helps!

Help plsssssss thanksss

Answers

60-___=59
60-1=59
So the 9 was distributed
(9x60)-(9x1)
9x1=9
So 540-9=531

Can anyone help me Factor.
81-25x^2

Answers

that is difference of two squares so the answer is (9-5x)(9+5x)

An adult elephant drinks about 225 liters of water each day. Is the number of days the water supply lasts proportional to the number of water the elephant drinks

Answers

Answer:

yes

Step-by-step explanation:

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