evaluate without multiplying directly :1) 103*107 2)95*96 3)104*96
xXSOHNIXx:
Do u mean by using identities ?
Answers
Answered by
26
1.) 103×107
(105-2)(105+2)
(105^2-2^2)
11025-4
11021
2.) 95×96
(95.5-0.5)(95+0.5)
(95.5^2-0.5^2)
9120.25-0.25
9120
3.)104×96
(100+4)(100-4)
(100^2-4^2)
10000-16
9984
(105-2)(105+2)
(105^2-2^2)
11025-4
11021
2.) 95×96
(95.5-0.5)(95+0.5)
(95.5^2-0.5^2)
9120.25-0.25
9120
3.)104×96
(100+4)(100-4)
(100^2-4^2)
10000-16
9984
Answered by
15
1) 103 x 104
SOLUTION] (100+3) x (100+4)
By using identity : (x+a)(x+b) =![x^{2} + (a+b) X x + ab x^{2} + (a+b) X x + ab](https://tex.z-dn.net/?f=+x%5E%7B2%7D+%2B+%28a%2Bb%29+X+x+%2B+ab)
=>![100^{2} + (7+3) X 100 + (3 X 7) 100^{2} + (7+3) X 100 + (3 X 7)](https://tex.z-dn.net/?f=+100%5E%7B2%7D+%2B+%287%2B3%29+X+100+%2B+%283+X+7%29)
=> 10000 + 1000 + 21
=>11021 [ANS]
2) 95 x 96
SOLUTION] (100-5) x (100-4)
By using identity : (x+a)(x+b) =![x^{2} + (a+b) X x + ab x^{2} + (a+b) X x + ab](https://tex.z-dn.net/?f=+x%5E%7B2%7D+%2B+%28a%2Bb%29+X+x+%2B+ab)
=>![100^{2} + {(-5)+(-4)} X 100 + (-5 X -4) 100^{2} + {(-5)+(-4)} X 100 + (-5 X -4)](https://tex.z-dn.net/?f=+100%5E%7B2%7D+%2B+%7B%28-5%29%2B%28-4%29%7D+X+100+%2B+%28-5+X+-4%29)
=> 10000 + (-900) + 20
=> 10000 - 900 + 20
=> 9120 [ANS]
3) 104 x 96
SOLUTION] (100+4) x (100-4)
By using identity: (x+y)(x-y) =![x^{2} - y^{2} x^{2} - y^{2}](https://tex.z-dn.net/?f=+x%5E%7B2%7D+-+y%5E%7B2%7D+)
=>![100^{2} - 4^{2} 100^{2} - 4^{2}](https://tex.z-dn.net/?f=+100%5E%7B2%7D+-+4%5E%7B2%7D+)
=> 10000 -16
=> 9984 [ANS]
HOPE IT HELPED YOU !!! IF SO, PLEASE MARK IT AS BRAINLIEST ;)
SOLUTION] (100+3) x (100+4)
By using identity : (x+a)(x+b) =
=>
=> 10000 + 1000 + 21
=>11021 [ANS]
2) 95 x 96
SOLUTION] (100-5) x (100-4)
By using identity : (x+a)(x+b) =
=>
=> 10000 + (-900) + 20
=> 10000 - 900 + 20
=> 9120 [ANS]
3) 104 x 96
SOLUTION] (100+4) x (100-4)
By using identity: (x+y)(x-y) =
=>
=> 10000 -16
=> 9984 [ANS]
HOPE IT HELPED YOU !!! IF SO, PLEASE MARK IT AS BRAINLIEST ;)
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