SOLUTION: I'm trying to help my niece with an algebra problem that has both of us stumped... (s+t)(s-t)(s+t)(s-t) The answer provided in her book is: s^4-2t^2s^2t^2 I can't even

Algebra.Com
Question 430834: I'm trying to help my niece with an algebra problem that has both of us stumped...
(s+t)(s-t)(s+t)(s-t)
The answer provided in her book is:
s^4-2t^2s^2t^2
I can't even get close to this answer. I got the s^4 and think I got the s^2 and t^2, but I can't figure out the -2t^2.
If you can tell me what I'm doing wrong, I'd appreciate it.
I came up with:
(s)(s)(s)(s) = s^4
(t)(-t)(t)(-t) = t^2
I am so confused right now, I don't know what to do. It's been years since I had Algebra.



Found 3 solutions by shree840, mananth, Alan3354:
Answer by shree840(260)   (Show Source): You can put this solution on YOUR website!
(s+t)(s-t)(s+t)(s-t) we will use formula s^2-t^2=(s+t)(s-t)
(s^2-t^2)(s^2-t^2)
s^4-2s^2y^2+t^4 ANS
how did you get T^2 when you multiply the t's

Answer by mananth(16946)   (Show Source): You can put this solution on YOUR website!
In identities there is a formula for the product of sum and difference of two variables.
(a+b)(a-b)=a^2-b^2
(s+t)(s-t)(s+t)(s-t)



Another formula is (a-b)^2= a^2-2ab+b^2
here a= s^2 & b=t^2

Answer by Alan3354(69443)   (Show Source): You can put this solution on YOUR website!
I'm trying to help my niece with an algebra problem that has both of us stumped...
(s+t)(s-t)(s+t)(s-t)
The answer provided in her book is:
s^4-2t^2s^2t^2
I can't even get close to this answer. I got the s^4 and think I got the s^2 and t^2, but I can't figure out the -2t^2.
If you can tell me what I'm doing wrong, I'd appreciate it.
I came up with:
(s)(s)(s)(s) = s^4
(t)(-t)(t)(-t) = t^2 ***** No, that's t^4, take another look.
---------------
s^4-2t^2s^2t^2 *** Either the book is wrong, or you copied it wrong.
-----------
The other tutors give the right answer.
One has a typo, and entered a "y" instead of a "t"

RELATED QUESTIONS

TRYING TO HELP MY SON W/ HIS HWK. PROBLEM:3N-T=S; SOLVE FOR... (answered by rcmcc)
Please help me A model rocket is launched with an initial upward velocity of 45 m/s. (answered by ewatrrr,greenestamps)
Find: sin (s+t), cos (s-t), tan (s+t), the quadrant of (s+t) Given: {{{ sin s = 3/5 }}} (answered by ikleyn)
Suppose S,T are subspaces of V and s intersect T=0. Show that every vector in S + T can... (answered by venugopalramana)
A stunt diver leaps off a bridge 50m above a river with an initial upward speed of 10m/s. (answered by ikleyn)
Word Problem Help A ball is thrown from an initial height of 4 feet with an initial... (answered by MathLover1)
could any one help me in my homework please =) suppose that S and T both are sets such (answered by drcole)
I am having trouble with this problem and could use some help.... (answered by algebra hello)
My problem is something is wrong with the equation. The instruction says to correct the... (answered by ankor@dixie-net.com)