#Can anyone explain these to me plz don’t just give the answers

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lavish tendon
reef pecanBOT
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dim dune
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@lavish tendon try drawing the triangle the fallen branch makes with the tree and label the angle and distance given

lavish tendon
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the issue is

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i found both legs of the right triangle to be equal

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because

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tan45=1

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and tan 30 doesnt include any variables

dim dune
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This is what you have right

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And we need to find the distance RG

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Rock ground

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And yes, you can use trig or geometry to find it

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Specifically cosine would help because it's formula includes the adjacent side (which is given to us as 12.3) and the hypotenuse, which we need to find

left pine
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yo can u help me after ur done

dim dune
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Another way would be to mirror the triangle at angle 30° to get an equilateral triangle. Then you can find the side from the formula for height

dim dune
left pine
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ok

lavish tendon
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let me show u

dim dune
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Okay and where is the stone

lavish tendon
dim dune
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I understood it as being on top of the tree, which would be y

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And z would be equal to y

lavish tendon
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in my diagram y is meant to be the height of the tree

lavish tendon
dim dune
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Im guessing you can find z

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y=x+12.3

dim dune
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The confusion for me here is the text. Its not clear to me whether the stone is on top of the tree, and whether the branch falls behind that 45° angle

lavish tendon
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i think

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the stone is on the floor

dim dune
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So right side of the line

lavish tendon
lavish tendon
lavish tendon
dim dune
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If the stone is on the floor where the tree is, then the distance to the branch where it touches the ground is just 12.3

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According to your image

dim dune
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Is the rock at the 90° angle?

lavish tendon
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no

lavish tendon
dim dune
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for the first one I don't know, still feels like you're assuming the rock is on the ground when it says the stone is on top of the tree. might be a language issue on my end.
for the second, turn cosec and sec into 1/sin and 1/cos and square them both

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@lavish tendon

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so $(\cos{A} - \csc{A})^2 + (\sin{A} - \sec{A})^2 = \left(\cos{A} - \frac{1}{\sin{A}}\right)^2 + \left(\sin{A} - \frac{1}{\cos{A}}\right)^2$

lavish tendon
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i tried this

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but

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after u simplify

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it doesnt give u smth thats part of the options

limpid spireBOT
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Ephesians 2:8-9

dim dune
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ok lets square them

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$\cos^2{A} - \frac{2\cos{A}}{\sin{A}} + \frac{1}{\sin^2{A}} + \sin^2{A} - \frac{2\sin{A}}{\cos{A}} + \frac{1}{\cos^2{A}}$

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is that right

limpid spireBOT
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Ephesians 2:8-9

lavish tendon
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js change the cos alpha to cos a

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ye

dim dune
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yeah got it

lavish tendon
dim dune
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ok, and you didn't get further than that?

lavish tendon
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then sin^2(x)+cos^2(x)=1

dim dune
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true

lavish tendon
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the middle terms

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i wrote as

dim dune
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$1 - \frac{2\cos{A}}{\sin{A}} + \frac{1}{\sin^2{A}} - \frac{2\sin{A}}{\cos{A}} + \frac{1}{\cos^2{A}}$

limpid spireBOT
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Ephesians 2:8-9

lavish tendon
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-2(cotx+tanx)

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for the middle terms

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i think that might have been a mistake

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but im not sure

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ik the maths is right

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but

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it might not be the approach ur meant to take

dim dune
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$1 - 2\left(\frac{\cos{A}}{\sin{A}}+\frac{\sin{A}}{\cos{A}}\right) + \frac{1}{\sin^2{A}} + \frac{1}{\cos^2{A}}$

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whoops

lavish tendon
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yep

dim dune
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try to find the common denominator for those fractions

lavish tendon
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U forgot then add 1/cos^2(x)

dim dune
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yeah just saw

limpid spireBOT
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Ephesians 2:8-9

dim dune
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anyways, try and find the common denominator

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and on top you will get 1

lavish tendon
dim dune
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for the second part yeah

lavish tendon
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oh

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ye i got it

dim dune
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great

lavish tendon
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so ur left with

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-2/cosasina

lavish tendon
dim dune
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$1 - 2\left(\frac{1}{\sin{A}\cos{A}}\right) + \frac{1}{\sin^2{A}\cos^2{A}}$

limpid spireBOT
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Ephesians 2:8-9

dim dune
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that's what you're left with right

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turn the 1/sinAcosA into sec and cosec

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same with the square

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and you should be able to turn it into one of the forms from the answers

lavish tendon
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So would it be

lavish tendon
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srry

dim dune
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not tan yeah

lavish tendon
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cosec

dim dune
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correct

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$1 - 2\sec{A}\csc{A} + \sec^2{A}\csc^2{A}$

limpid spireBOT
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Ephesians 2:8-9

lavish tendon
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OHH

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I GET IT NOW

dim dune
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$1 - 2\sec{A}\csc{A} + (\sec{A}\csc{A})^2$ maybe that makes it easier to see what it is

limpid spireBOT
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Ephesians 2:8-9

lavish tendon
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thank you sm

dim dune
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np, sorry about the first problem though

lavish tendon
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all good

lavish tendon
ripe skiffBOT
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@lavish tendon has given 1 rep to @dim dune

dim dune
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yw anytime

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feel free to repost the first problem, I don't think anyone will look in here

lavish tendon
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i will

dim dune
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+close