Factorise 5x^2 - 7y^2
Without finding cube factorise :-
(i) (2r - 3s )^3 + (3s - 5t)^3 + (5t - 2r)^3
(ii) (-3/4)^3 + (-5/8)^3 + (11/8)^3
Answers
Answered by
1
5x^2-7y^2
=(√5 x)^2-(√7 y)^2
=(√5 x-√7 y)(√5 x+√7 y)
(2r - 3s )^3 + (3s - 5t)^3 + (5t - 2r)^3
*(2r-3s+3s-5t+5t-2r)=0
=>a+b+c=0
a^3+b^3+c^3=3(a)(b)(c)
=3(2r-3s)(3s-5t)(5t-2r)
(-3/4)^3 + (-5/8)^3 + (11/8)^3
*-3/4-5/8+11/8=0
=>a+b+c=0
a^3+b^3+c^3=3(a)(b)(c)
=3(-3/4)(-5/8)(11/8)
=(√5 x)^2-(√7 y)^2
=(√5 x-√7 y)(√5 x+√7 y)
(2r - 3s )^3 + (3s - 5t)^3 + (5t - 2r)^3
*(2r-3s+3s-5t+5t-2r)=0
=>a+b+c=0
a^3+b^3+c^3=3(a)(b)(c)
=3(2r-3s)(3s-5t)(5t-2r)
(-3/4)^3 + (-5/8)^3 + (11/8)^3
*-3/4-5/8+11/8=0
=>a+b+c=0
a^3+b^3+c^3=3(a)(b)(c)
=3(-3/4)(-5/8)(11/8)
Answered by
0
Answer:
Step-by-step explanation:
Attachments:
Similar questions