Please explain why x^2 • -x^-2 = -1?
回答 (6)
2016-10-05 6:01 pm
✔ 最佳答案
since x^-2 = 1/x^2so x^2 • -x^-2 = x^2 • -1/x^2 = -1
2016-10-05 6:04 pm
By indice law : a⁻ⁿ = 1/aⁿ
Hence, x⁻² = 1/x²
L.H.S.
= x² • -x⁻²
= x² • (-1) • x⁻²
= (-1) • x² • x⁻²
= (-1) • x² • (1/x²)
= (-1) • (x²/x²)
= (-1) • 1
= -1
= R.H.S.
Hence, x² • -x⁻² = -1
Hence, x⁻² = 1/x²
L.H.S.
= x² • -x⁻²
= x² • (-1) • x⁻²
= (-1) • x² • x⁻²
= (-1) • x² • (1/x²)
= (-1) • (x²/x²)
= (-1) • 1
= -1
= R.H.S.
Hence, x² • -x⁻² = -1
2016-10-05 6:21 pm
x^2 * -x^-2 can also be written as x^2/-x^2 which is equal to -1
2016-10-05 6:05 pm
x² • −x⁻²
= x² • −1/x²
= (x²/x²) • −1
= 1 • −1
= −1
2016-10-05 6:00 pm
Well,
this is not correct
x^2 * x^-2 = x^(2 - 2) = x^0 = 1
hope it' ll help !!
this is not correct
x^2 * x^-2 = x^(2 - 2) = x^0 = 1
hope it' ll help !!
2016-10-05 6:49 pm
Note that this is only true if x is not zero
收錄日期: 2021-04-18 15:42:13
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