thx guys
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Answer:
1x10⁻¹m
Step-by-step explanation:
y = 3x10⁸/x
x is wavelength
y is frequency
what is the wavelength if frequency is 3 x10⁹= y
y = 3x10⁸/x
3 x10⁹ = 3 x10⁸/x
make x the subject of formula
3 x10⁹x = 3 x10⁸
divide both sides by 3 x10⁹
x = 3 x10⁸/3 x10⁹
Adopting law of indices
xᵃ/xᵇ = xᵃ⁻ᵇ
3¹⁻¹x10⁸⁻⁹ = 3⁰x10⁻¹ = 1x10⁻¹m