Pls solve.

Asked by pb_ckt | 12th Jun, 2019, 02:48: PM

Expert Answer:

begin mathsize 16px style Since space straight A space lies space in space the space 3 to the power of rd quadrant space then space straight pi less or equal than straight A less or equal than fraction numerator 3 straight pi over denominator 2 end fraction space straight i. straight e space 180 to the power of 0 less or equal than straight A less or equal than 270 to the power of 0
3 tanA space minus space 4 space equals space 0 space space space space space..... space Given
rightwards double arrow space tanA space equals space 4 over 3 space equals space fraction numerator Opposite space side space space over denominator Adjacent space side end fraction
rightwards double arrow Opposite space side left parenthesis Perpedicular right parenthesis space equals space 4 space and space Adjacent space side left parenthesis Base right parenthesis space equals space 3
By space Pythagoras space Theorem comma space we space get
open parentheses Hypotenuse close parentheses squared space equals space left parenthesis Perpedicular right parenthesis squared space plus space left parenthesis Base right parenthesis squared space
space space space space space space space space space space space space space space space space space space space space space space equals space left parenthesis 4 right parenthesis squared space plus space left parenthesis 3 right parenthesis squared
space space space space space space space space space space space space space space space space space space space space space space equals space 16 space plus space 9
space space space space space space space space space space space space space space space space space space space space space space space equals space 25
rightwards double arrow Hypotenuse space equals space plus-or-minus 5
The space values space of space sin space and space cos space in space the space third space quadrant space is space always space negative.
rightwards double arrow Hypotenuse space left parenthesis straight H right parenthesis equals space minus 5
sinA space equals space straight P over straight H space equals space fraction numerator 4 over denominator negative 5 end fraction space and space cosA space equals space straight B over straight H space equals space fraction numerator 3 over denominator negative 5 end fraction
To space find colon space 3 space sinA space plus space 4 space cosA space
equals space space 3 space cross times fraction numerator 4 over denominator negative 5 end fraction space plus space 4 space cross times space space fraction numerator 3 over denominator negative 5 end fraction
equals fraction numerator negative 12 space minus space 12 over denominator 5 end fraction
equals space minus 24 over 5
Answer colon space Option space straight B
end style

Answered by Yasmeen Khan | 13th Jun, 2019, 11:14: AM