At vero eos et accusamus et iusto odio dignissimos ducimus qui blanditiis praesentium voluptatum deleniti atque corrupti quos dolores et quas molestias excepturi sint occaecati cupiditate non provident, similique sunt in culpa qui officia deserunt mollitia animi, id est laborum et dolorum fuga.
Et harum quidem rerum facilis est et expedita distinctio. Nam libero tempore, cum soluta nobis est eligendi optio cumque nihil impedit quo minus id quod maxime placeat facere possimus, omnis voluptas assumenda est, omnis dolor repellendus.
Itaque earum rerum hic tenetur a sapiente delectus, ut aut reiciendis voluptatibus maiores alias consequatur aut perferendis doloribus asperiores repellat.

Get our expert's

answer on brainly

SEE EXPERT ANSWER

Get your **free** account and access **expert** answers to this and **thousands** of other questions.

I got my questions answered at brainly.com in under 10 minutes. Go to brainly.com now for free help!

Get this expert

answer on brainly

SEE EXPERT ANSWER

Get your **free** account and access **expert** answers to this and **thousands** of other questions

use sin A-sin B formula, do u know it ?

the sin(A+B)?

nopes, sin A - sin B
on sin(x+h) - sin x.

us, would you expand sin(x+h)?

*um

how does sinA-sinB work?

sorry, don't know sinA-sinB = 2 cos((A+B)/2)sin((A+B)/2)

It's... actually \[sinA - sinB = 2cos\frac{A+B}{2}sin\frac{A-B}{2}\]

Q: Is that the product to sums formula?

then u better go with sin(x+h) = sin x cos h + cos x sin h ....

sum-to-product indeed.

Hmmm... Isn't it lim x->0 (1-cos x)/x = 0?

isn't it lim h->0?

made a mistake....wait.yup its 0,sorry.

but basically u need to separate the numerator in 2 limits.

so your 1st limit will be 0 as pointed out correctly and 2nd limit will be just cos x *1 = cos x

how are theses limits calculated?

*limits

yeah um, how are these proven? (Sorry if I'm being a bit fussy)

maybe later... just send me the links

Oh yeah, MIT OCW is good. Does this show the whole d/dx sin(x)?

Yup!

thanks...turns out I downloaded this ages ago, but stopped after lecture 2 and jumped about places

Thanks a heap. Can you show me how sinA-sinB = ...

Do you know how to work out the product-to-sum formula?

whats that?

Example: sinAcosB = (1/2) [ sin(A+B) +sin(A-B)]

sorry, no

hartnn explained, I think :)

so whats sin(x+y) - sin (x-y)= ?

sin(x)cos(y)+cos(x)sin(y)-sin(x)cos(y)+cos(x)sin(y) = 2cos(x)sin(y)

um, no

x+y=A
x-y=B
Adding x+x=A+B --->x=(A+B)/2
i think y can can find now...

(A+B)/2+y=A
y=(A-B)/2

yup, any more doubts?

uh, so does that mean sin(A)-sin(B)=2cos((A+B)/2)sin((A-B)/2)

exactly, yes.

OK, thank you