Step-by-step explanation:
[tex]8. log_{10}(2.15) = 0.332 \: then \: log_{10}(21500) = ..... \\ log(21500) = log(2.15 \times 10000) \\ = log(2.15) + log(10000) \\ = log_{10}(2.15) + log_{10}( {10}^{4} ) \\ = 0.332 + 4 log_{10}(10) \\ = 0.332 + 4(1) \\ log_{10}(21500) = 4.332[/tex]
9. log(2)=a, log(3)=b, then log(36)=______
log(36) = log(6*6) = log(6) + log(6)
log(36)= log(6) + log(6)
log(36) = log(3*2) + log(3*2)
log(36) = (log(3) + log(2)) + (log(3) + log(2))
log(36) = (a + b) + (b + a)
log(36) = a + b + b + a
log(36) = 2a + 2b
