A community for students.
Here's the question you clicked on:
 0 viewing
anonymous
 one year ago
.
anonymous
 one year ago
.

This Question is Closed

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3x^2 + 64 this is a like the difference of 2 squares except you have to use the imaginary number i remember that i^2 = 1 so can you fit the i values in here x^2 + 64 = ( x + ____)( x  ____)

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3ok what is the square root of 64?

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3ok so expand this and see if it comes back to x^2 + 64 (x + 8i)(x  8i)

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3just as in difference of 2 squares the middle terms will cancel out

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0okayy.... so that is the first one

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3(x + 8i)(x  8i) = x^2 + 8ix  8ix 64*1 = x^2 + 64

welshfella
 one year ago
Best ResponseYou've already chosen the best response.316x^2 + 49 handle it in the same way

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3take square root of 16x^2 and 49

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3No  where are the i's???

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3and you take Square root of 16x^2

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0well its 4, but idk what to do with it

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3it 4x 4x * 4x = 16x^2

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3put 4x in each bracket

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3yes (16x + 7i)(x  7i) would not come back to 4x^2 + 64 because the 2 terms in ix would not cancel out

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0next ones a bit different

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3Oh no thats not quite right Look at your signs  doddnt forget its like difference of 2 squares

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0sorry lol i copy and pasted the wron egquation

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0i wanted to copy then change the signs but i copied the wrong one

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3dont know why but i can't copy and paste!

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Find the product of (x + 9i)^2. next one

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3withe the last 3 you just expand the parentheses in the normal way (x + 9i)(x + 9i) first multiply the second bracket by x then multiply it by 9i = x(x + 9i) + 9i(x + 9i) = x^2 + 9xi + 9xi + ? can you do the last bit?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0sorry i really tired today

welshfella
 one year ago
Best ResponseYou've already chosen the best response.381* i^2 and what is i^2 equal to?

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3so that is 81 * 1 = 81 x^2 + 9xi + 9xi  81 now just add the 2 middle like terms

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3right giving x^2 + 18xi  81

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3Yes the 4 th one is done in exactly the same way

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0can u just set it up (expand it) and ill take from their then you check?

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3(x  2i)(x  2i) = x(x  2i)  2i(x  2i)

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3right so up until the last term 2i*2i is not 2i^2  *  = + and 2*2 = 4

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3treat i as if it weer an x or a y x^x = x^2 i* i = ?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0what do you mean by equals?

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3i^2 = 1 so 4i^2 = ?

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3important to remember i = sqrt(1) so i^2 = 1

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3x^22xi2xi4 = x^2  4xi  4

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0so is that the answer cause it says to find the product

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3yes the last one is more complicated because the last term in the brackets is (3x + 5i) so you could do the last part (3x + 5i)^2 first then plug it in later

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3you can do this in the same way as the last 2 (3 + 5i)(3 + 5i) = 3(3 + 5i) + 5i(3 + 5i) ok try and do that

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3yea good job and we can simplify it further to 30i  16

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0is that the answer to the problem?

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3No we have to plug that in to the expansion (x + (3+5i)(x + (3+5i) = x(x + (3+5i) + (3 + 5i)(x + (3+5i) = x^2 +3x + 5xi + 3x + 9 + 15i + 30i 16

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3hold on  I'm getting tired to thats wrong

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3x(x + (3+5i) + (3 + 5i)(x + (3+5i) = x^2 + 3x + 5xi + 3x + 5xi + 30i  16

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3thats it now simplify that was a tricky one

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Thanks thats it for now

welshfella
 one year ago
Best ResponseYou've already chosen the best response.3good I think I'll take a break lol
Ask your own question
Sign UpFind more explanations on OpenStudy
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.