Logs, natural logs and e
The calculator uses gfor log base 10 and hfor log base e. You don’t have to remember which button is which. All you need to do is look at the second function above each button. The gbutton has Gabove it reminding you that the gbutton is base 10. Similarly the hbutton has Habove it. his base e.
1Use your calculator to evaluate each expression correct to 3 decimal places.
A | log10 105 | B | loge 8 | C log10 0.6 |
D | loge 0.5 | E | log10 (4.3× 2.5) | F 4loge 209 |
2A Enter loge (−1) into your calculator.
B Explain why your calculator displays the message “Math ERROR”.
3Your calculator has two e buttons. You can find the value of e as the alpha function on K. The value of ex can be determined by using the second function on h.
A Determine the value of e using Q K p. Answer to 4 decimal places. B Find the value of e3 to 2 decimal places by pressing SHIFTh3.
1.Determine the following values correct to 2 decimal places.
A e2.5 | B e−1 | C e |
4Calculate the values of the following expressions.
A | loge | e2 | B loge e3 | C loge e |
D | loge | e−1 | F log10 100 | G log10 10−1 |
5What is the value of loge en ? (You’ll have to use your brain for this one!)
6Evaluate 800e12k when k = 0.4. Express your answer to the nearest hundred.
7Determine the value of 950e−10k when k = 1.4.Express your answer in scientific notation with 3 significant figures.
8What is the value of π e? Express your answer to 2 decimal places.
Answers |
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1A 2.021 | B 2.079 | C −0.222 | D −0.693 | E 1.031 | F 21.369 | ||
2 log x only exists for x > 0. | 3A 2.7183 | B 20.09 4A 12.18 B 0.37 C 2.72 | |||||
5A 2 B 3 | C 1 | D −1 | E 2 | F −1 | 6 n | 7 97 200 | 8 7.90×10−4 9 8.54 |
© Sue Thomson and Shriro Australia PTY Limited. This page may be photocopied for classroom use.
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