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Q. Evaluate: (313 x 313 + 287 x 287).
Read Solution (Total 16)
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- 313 x 313 + 287 x 287
=(313)^2+(287)^2
=(300+13)^2+(300-13)^2
=2(300^2+13^2) since,(a+b)^2+(a-b)^2=2(a^2+b^2)
=2(90000+169)
=180000+ 338
=180338 - 10 years agoHelpfull: Yes(71) No(0)
- (313 x 313 + 287 x 287) = a^2+b^2
= (a+b)^2-2ab
= 600^2-179662
= 360000-179662
= 180338 ans.. - 10 years agoHelpfull: Yes(11) No(2)
- 300+13*300+13 + 300-13*300-13
(a+b)^2 + (a-b)^2 = 2(a^2+ b^2)
=2(300^2+13^2)
=2(90000+169)
=180000+ 338
=180338 - 10 years agoHelpfull: Yes(5) No(0)
- 180338
slove by using bdmos rule
- 10 years agoHelpfull: Yes(1) No(6)
- clearly its a^2 + b^2 =1/2{(a+b)^2+(a-b)^2}
=1/2{(313+287)^2+(313-287)^2}
=180338 - 10 years agoHelpfull: Yes(1) No(0)
- 313*313=97969
287*287=82369
total =180338
so my ans is 180338 - 10 years agoHelpfull: Yes(1) No(5)
- (a*a+b*b)=(a^2+b^2)
(a^2+b^2)=1/2((a+b)^2+(a-b)^2)
so,a=313,b=287
then 1/2((313+287)^2+(313-287)^2)=1/2((600)^2+(26)^2)=1/2(360000+676)=180338 - 10 years agoHelpfull: Yes(1) No(0)
- (300+13)^2+(300-13)^2=2138
- 10 years agoHelpfull: Yes(1) No(0)
- ((300+13)^2+(300-13)^2)
300^2+13^2+2(13)(300)+300^2+13^2-2(13)(300)
2(90000)+2(169)
180000+338
=180338 - 10 years agoHelpfull: Yes(1) No(0)
- 300+13*300+13 + 300-13*300-13
(a+b)^2 + (a-b)^2 - 10 years agoHelpfull: Yes(0) No(0)
- 97969+82369=180338
- 10 years agoHelpfull: Yes(0) No(2)
- [(a+b)^2+(a-b)^2]/2=a^2+b^2
here a=313 b=287
(a+b)^2=(313+287)^2=360000 (a-b)^2=(313-287)^2=676
360000+676=360676
360676/2=180338 - 10 years agoHelpfull: Yes(0) No(0)
- 313=(300+13) or (326-13) so 313^2=(300*326)+13^2=97969
287=(300-13) or (274+13) so 287^2=(300*274)+13^2=82369
so 313*313 + 287*287 = 180338
this rule is applicable to calculating the square of any number. - 10 years agoHelpfull: Yes(0) No(0)
- a^2+b^2=(a+b)^2-2ab
s0 a=313,b=287
sol: 180338 - 10 years agoHelpfull: Yes(0) No(0)
- a^2+b^2=(a-b)^2+2ab...so...676+2*313*287=
89831*2=179662+676=180338 - 10 years agoHelpfull: Yes(0) No(0)
- a*a+(b*b)=a2+b2 so (313+287)2= 600)2= 360000
- 7 years agoHelpfull: Yes(0) No(0)
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