Mathematics: Post your doubts here!

[techgeek]

kindly help with part 1 of this question.

Collect the information given:

probability that children jump higher than 127 cm is 8/10 = 0.8

probability that children jump higher than 135 cm is 1/3= 0.333

Applying normal distribution as usual:

for 127 cm:

P (X> 127) = 1 - ϕ (127-μ) /σ

0.8 = 1 - ϕ (127-μ) /σ


for 135 cm:

P (X> 135) = 1 - ϕ (135-μ) /σ

0.333 = 1 - ϕ (135-μ) /σ


When you solve these two you end up with two equations:

μ=127 + 0.842σ

and μ=135 - 0.431 σ


Solving these two simultaneously:
you'll get
σ= 6.28

and

μ=132

 

[taimurahmed]

Can someone help me do this question

 

[mohmed ahmed soliman]

can ..just click on "shift" and then "mode"
option 3: De

suppose i have 135 degree angle and i want to convert to radian
i know how to do that by math but i want a faster way
also how to use calculator for differentiation and ingegration qs

 

[mohmed ahmed soliman]

7 > 4-3sinx > 1

ok thanks but how to do part v

 

[mohmed ahmed soliman]

1/2 pi = 90°
Tan (90-x) = sin (90-x)/cos (90-x)
But sin (90-x)= cosx and cos (90-x)= sinx
So tan (90-x) = cosx/sinx = 1/tan x = 1/k

which trigonometry formulas should i know for those qs

 

[mistique_bee]

suppose i have 135 degree angle and i want to convert to radian
i know how to do that by math but i want a faster way
also how to use calculator for differentiation and ingegration qs

yeah..just do the same thing i told before..click on shift..mode(the one with the power button) and 4 for radians..
for differentiation and intergration i'll give u a video..its easy u will get it

 

[mistique_bee]

which trigonometry formulas should i know for those qs

U have to use trigonometric identities....

 

[mistique_bee]

suppose i have 135 degree angle and i want to convert to radian
i know how to do that by math but i want a faster way
also how to use calculator for differentiation and ingegration qs

here u go..hope it helps

 

[techgeek]

ok thanks but how to do part v

For g-1 (3), we first need g-1 (x) first. To find that, we first make x the subject instead of y.

g(x) = 4 -3 sinx

y = 4 - 3 sin x

x = (4-y) / 3

but this is g^-1 y not g-1 (x), replace y with x in the formula we made and we'd get g-1 (x)

g-1 (x) = (4-x)/3

g-1 (3) = sin-1 (4 - 3)/4 = sin-1 1/4 = 2.80

 

[techgeek]

Can someone help me do this questionView attachment 60318

You are given mean, sd. and that books greater than 29 are large. You can first use normal approximation to find the probability of the books that are larger than 29 cm.
The answer you get is actually the success, p of getting a book which is large. q=1-p with p, q and n as 8, you can simply use binomial distribution for
P(X=0) + P(X=1)

 

[osama ahmed ibrahim]

= sin (90-x)/cos (90-x)
But sin (90-x)= cosx and

i am not good in trigonometry which rules should i know for this qs
i know that cos90-x=sinx
sin90-x=cosx
tan90-x=1/tanx

is this enough

 

[Saad the Paki]

i am not good in trigonometry which rules should i know for this qs
i know that cos90-x=sinx
sin90-x=cosx
tan90-x=1/tanx

is this enough

which trigonometry formulas should i know for those qs

A few more :
sin 180-x = sin x
cos 180-x = -cosx
sin 90+x = cosx
cos 90+x = -sinx
sin 180+x = -sinx
cos 180+x = -cosx

For tan use the identity tan x =sin x/cos x.

 

[osama ahmed ibrahim]

x = -cosx
sin 90+x = cosx
cos 90+x = -sinx
sin 180+x = -si

thanks

 

[osama ahmed ibrahim]

u go..hope it hel

thanks

 

[osama ahmed ibrahim]

+x = cosx
cos 90+x = -sinx
sin 180+x =

my math teacher wrote sin90+x=cosx
cos(90+x)=-sinx
tan(90+x)=-1/tanx
is he right or he made a msitake!

 

[osama ahmed ibrahim]

i didnt take this log function is as so what to do
do u have a log function for ur video
i want someone to clarify the work

 

[The Sarcastic Retard]

View attachment 60324 View attachment 60325 View attachment 60325i didnt take this log function is as so what to do
do u have a log function for ur video
i want someone to clarify the work

I gave u a link, didn't it helped u?

 

[osama ahmed ibrahim]

I gave u a link, didn't it helped u?

yes but it s a complete chapter i dont have time and i am not willing to give it all this effort to do the q.

 

[osama ahmed ibrahim]

d u?

just i want to know how to do this q using log
i dont need all application of log function

 

[osama ahmed ibrahim]

.