Express Cosx-3Sinx in form Rcos(x+a) and show that cosx-3sinx=4 has no solution MEI OCR June 2016 C4

Cosx-3sinx =R(CosxCosa-SinxSina) 1=Rcosa R^2=1^2+3^2  r=(10)^0.5=(approx)3.16 a=1.249 3.16Cos(x+1.249)=4 has no solution as 4<3.16 so as cos(theta) has maximum value of 1, there are no solutions

JP

Related Maths A Level answers

All answers ▸

If we have a vector 4x + 6y + z and another vector 3x +11y + 2z then what is the angle between the two?Give the answer in radians


How do you solve a quadratic inequality eg find the values of x for which x^2 -6x +2 < -3


Write down the coordinates of the centre and the radius of the circle with equation x^2+y^2-4x-8y+11=0


How does the product rule for differentiation work