Answer:cos( A + B ) = cosAcosB - sinAsinB ;
cos( A + B ) / ( cosAsinB ) = ( cosAcosB - sinAsinB ) / ( cosAsinB ) = ( cosAcosB ) / ( cosAsinB ) - ( sinAsinB ) / ( cosAsinB ) = cosB / sinB - sinA / cosA = cotB - tanA ;
tan²(x) - sin²(x) = sin²(x)/cos²(x) - sin²(x)
… = sin²(x) (1/cos²(x) - 1)
… = sin²(x) (sec²(x) - 1)
… = sin²(x) tan²(x)
Step-by-step explanation:
Answer:
4
Step-by-step explanation:
use the Pythagoras' theorem
formula for an ABC triangle( right angled)
AB is height
BC is hypotenuse
CA is length
= 
+ 
in your case
AB is 7
BC is 8
CA is unknown so we write x
=
+
64=49+
64-49=
15=
=x
3.87=x
4=x
Answer:
D
Step-by-step explanation:
Any number multiplied by an even number will always be even. 10 is an even number.
That's the ratio of 4,126,532 to 1,000,000 so it's rational.
Here's a little factoid that I never see mentioned anywhere, but I think it can be really helpful to know:
==> Any number that you can WRITE DOWN COMPLETELY using digits (plus a decimal point or a fraction bar if you need them) is a rational number.
If " 4.126532 " is the whole thing, you sure nuff wrote it down, so it's rational.
