Logarithmic Functions Mrs. King Pre-Calculus
What are logarithms? The inverse of the exponential function!
Graph: Picture from: Regardless of the base, the exponential graph goes through the point (0,1). Therefore, regardless of the base, the logarithmic graph goes through the point (1,0).
Definitions of Logarithms The logarithmic function is the function, where b is any number such that is equivalent to The function is read "log base b of x".
10 3 = 1000log = = 16log 2 16 = = 10,000log = = 9log 3 9 = = 16log 4 16 = = 0.01log = -2 p = q 2 log q p = 2 x y = 2log x 2 = y p q = rlog p r = q pifactory.net/catalog/files/teacher_resources/.../logarithms_01.ppt Rewrite using logarithms
10 3 = 1000log = = 16log 2 16 = = 10,000log = = 9log 3 9 = = 16log 4 16 = = 0.01log = -2 p = q 2 log q p = 2 x y = 2log x 2 = y p q = rlog p r = q pifactory.net/catalog/files/teacher_resources/.../logarithms_01.ppt Rewrite using logarithms
10 3 = 1000log = = 16log 2 16 = = 10,000log = = 9log 3 9 = = 16log 4 16 = = 0.01log = -2 p = q 2 log q p = 2 x y = 2log x 2 = y p q = rlog p r = q pifactory.net/catalog/files/teacher_resources/.../logarithms_01.ppt Rewrite using logarithms
10 3 = 1000log = = 16log 2 16 = = 10,000log = = 9log 3 9 = = 16log 4 16 = = 0.01log = -2 p = q 2 log q p = 2 x y = 2log x 2 = y p q = rlog p r = q pifactory.net/catalog/files/teacher_resources/.../logarithms_01.ppt Rewrite using logarithms
10 3 = 1000log = = 16log 2 16 = = 10,000log = = 9log 3 9 = = 16log 4 16 = = 0.01log = -2 p = q 2 log q p = 2 x y = 2log x 2 = y p q = rlog p r = q pifactory.net/catalog/files/teacher_resources/.../logarithms_01.ppt Rewrite using logarithms
10 3 = 1000log = = 16log 2 16 = = 10,000log = = 9log 3 9 = = 16log 4 16 = = 0.01log = -2 p = q 2 log q p = 2 x y = 2log x 2 = y p q = rlog p r = q pifactory.net/catalog/files/teacher_resources/.../logarithms_01.ppt Rewrite using logarithms
10 3 = 1000log = = 16log 2 16 = = 10,000log = = 9log 3 9 = = 16log 4 16 = = 0.01log = -2 p = q 2 log q p = 2 x y = 2log x 2 = y p q = rlog p r = q pifactory.net/catalog/files/teacher_resources/.../logarithms_01.ppt Rewrite using logarithms
10 3 = 1000log = = 16log 2 16 = = 10,000log = = 9log 3 9 = = 16log 4 16 = = 0.01log = -2 p = q 2 log q p = 2 x y = 2log x 2 = y p q = rlog p r = q pifactory.net/catalog/files/teacher_resources/.../logarithms_01.ppt Rewrite using logarithms
10 3 = 1000log = = 16log 2 16 = = 10,000log = = 9log 3 9 = = 16log 4 16 = = 0.01log = -2 p = q 2 log q p = 2 x y = 2log x 2 = y p q = rlog p r = q pifactory.net/catalog/files/teacher_resources/.../logarithms_01.ppt Rewrite using logarithms
10 3 = 1000log = = 16log 2 16 = = 10,000log = = 9log 3 9 = = 16log 4 16 = = 0.01log = -2 p = q 2 log q p = 2 x y = 2log x 2 = y p q = rlog p r = q pifactory.net/catalog/files/teacher_resources/.../logarithms_01.ppt Rewrite using logarithms
log 4 64 = 34 3 = 64 log 3 27 = 33 3 = 27 log 36 6 = 1 / /2 = 6 log 12 1= = 1 log x y = zx z = y log a 5 = ba b = 5 log p q = rp r = q c = log a bb = a c pifactory.net/catalog/files/teacher_resources/.../logarithms_01.ppt Rewrite using exponential notation
log 4 64 = 34 3 = 64 log 3 27 = 33 3 = 27 log 36 6 = 1 / /2 = 6 log 12 1= = 1 log x y = zx z = y log a 5 = ba b = 5 log p q = rp r = q c = log a bb = a c pifactory.net/catalog/files/teacher_resources/.../logarithms_01.ppt Rewrite using exponential notation
log 4 64 = 34 3 = 64 log 3 27 = 33 3 = 27 log 36 6 = 1 / /2 = 6 log 12 1= = 1 log x y = zx z = y log a 5 = ba b = 5 log p q = rp r = q c = log a bb = a c pifactory.net/catalog/files/teacher_resources/.../logarithms_01.ppt Rewrite using exponential notation
log 4 64 = 34 3 = 64 log 3 27 = 33 3 = 27 log 36 6 = 1 / /2 = 6 log 12 1= = 1 log x y = zx z = y log a 5 = ba b = 5 log p q = rp r = q c = log a bb = a c pifactory.net/catalog/files/teacher_resources/.../logarithms_01.ppt Rewrite using exponential notation
log 4 64 = 34 3 = 64 log 3 27 = 33 3 = 27 log 36 6 = 1 / /2 = 6 log 12 1= = 1 log x y = zx z = y log a 5 = ba b = 5 log p q = rp r = q c = log a bb = a c pifactory.net/catalog/files/teacher_resources/.../logarithms_01.ppt Rewrite using exponential notation
log 4 64 = 34 3 = 64 log 3 27 = 33 3 = 27 log 36 6 = 1 / /2 = 6 log 12 1= = 1 log x y = zx z = y log a 5 = ba b = 5 log p q = rp r = q c = log a bb = a c pifactory.net/catalog/files/teacher_resources/.../logarithms_01.ppt Rewrite using exponential notation
log 4 64 = 34 3 = 64 log 3 27 = 33 3 = 27 log 36 6 = 1 / /2 = 6 log 12 1= = 1 log x y = zx z = y log a 5 = ba b = 5 log p q = rp r = q c = log a bb = a c pifactory.net/catalog/files/teacher_resources/.../logarithms_01.ppt Rewrite using exponential notation
log 4 64 = 34 3 = 64 log 3 27 = 33 3 = 27 log 36 6 = 1 / /2 = 6 log 12 1= = 1 log x y = zx z = y log a 5 = ba b = 5 log p q = rp r = q c = log a bb = a c pifactory.net/catalog/files/teacher_resources/.../logarithms_01.ppt Rewrite using exponential notation
log 4 64 = 34 3 = 64 log 3 27 = 33 3 = 27 log 36 6 = 1 / /2 = 6 log 12 1= = 1 log x y = zx z = y log a 5 = ba b = 5 log p q = rp r = q c = log a bb = a c pifactory.net/catalog/files/teacher_resources/.../logarithms_01.ppt Rewrite using exponential notation
The Change of Base Formula
Examples…watch your parenthesis!